Contents

1. M78 Auto T/M

2. Appendix I
- CDPF
- Locking Differential
3. Appendix II
- Trouble shooting
- S/Bulletin (2006~2008)
- T/Information (2006~2008)
M78 Auto T/M

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Table of Contents
M78 Automatic transmission ..........................................................................................................................1

1 System Operation...................................................................................................................................4
1.1 General Description............................................................................................................................................... 4
1.2 Advanced Six Speed Features.............................................................................................................................. 5
Early Downshifts with Hard Braking and Skip Shifts ......................................................................................... 5
Gear Hold Going Uphill/Downhill.......................................................................................................................... 5
Upshift Prevention with Fast-off Accelerator Pedal............................................................................................ 5
Drive and Reverse Engagement ........................................................................................................................... 5
Converter Clutch Lock-Up In All Gears................................................................................................................ 5
Embedded Memory Module .................................................................................................................................. 5
1.3 Transmission Cooling ........................................................................................................................................... 6
1.4 Shift Strategy.......................................................................................................................................................... 6
Gear Change........................................................................................................................................................... 6
Coastdown.............................................................................................................................................................. 6
Torque Demand...................................................................................................................................................... 6
Range Mode (Manual Mode).................................................................................................................................. 6
st
1 Gear State .......................................................................................................................................................................... 6
nd
2 Gear State ......................................................................................................................................................................... 6
rd
3 Gear State.......................................................................................................................................................................... 6
th
4 Gear State .......................................................................................................................................................................... 6
th
5 Gear State .......................................................................................................................................................................... 6
th
6 Gear State .......................................................................................................................................................................... 6
1.5 Transmission Components................................................................................................................................... 7
Gear Train ............................................................................................................................................................... 7
Single Planetary Gear-set ..................................................................................................................................... 8
Double Planetary.................................................................................................................................................... 8
Clutches and Brake Bands.................................................................................................................................... 9
Torque Converter................................................................................................................................................... 9
Torque Converter Lock-up Clutch...................................................................................................................... 10
Fluid Pump ........................................................................................................................................................... 11
1.6 Hydraulic Schematics.......................................................................................................................................... 12
Overall Hydraulic Circuit ..................................................................................................................................... 12
Gear Fluid Flow Schematics ............................................................................................................................... 14
st
1 Gear Power Path Ratio 3.53:1..................................................................................................................................... 14
st
Manual 1 Gear Power Path Ratio 3.53:1 ........................................................................................................................ 14
nd
2 Gear Power Path Ratio 2.14:1 .................................................................................................................................... 14
rd
3 Gear Power Path Ratio 1.48:1..................................................................................................................................... 15
th
4 Gear Power Path Ratio 1.16:1..................................................................................................................................... 15
th
5 Gear Power Path Ratio 0.87:1..................................................................................................................................... 15
th
6 Gear Power Path Ratio 0.68:1..................................................................................................................................... 16
Reverse Gear Power Path Ratio 3.09:1 ........................................................................................................................... 16
Neutral................................................................................................................................................................................... 16
Park ....................................................................................................................................................................................... 17
1.7 Transmission Electronic Control System .......................................................................................................... 17
Transmission Control Unit .................................................................................................................................. 17
Communication Network..................................................................................................................................... 18
Embedded Memory Module ................................................................................................................................ 18
Solenoid Valves and Variable Bleed Solenoids ................................................................................................ 19
Sensor Inputs ....................................................................................................................................................... 20
Brake Pedal Position Switch ................................................................................................................................................. 20
Engine Intake Temperature Sensor ...................................................................................................................................... 20
Barometric Pressure Sensor ................................................................................................................................................. 20
Accelerator Pedal Position Sensor........................................................................................................................................ 20
Input Shaft Speed Sensor ..................................................................................................................................................... 20
Output Shaft Speed Sensor .................................................................................................................................................. 20
Transmission Fluid Temperature Sensor .............................................................................................................................. 21
Inhibitor Switch...................................................................................................................................................................... 21
Transmission Control Monitoring System......................................................................................................... 21
Supply Monitoring ................................................................................................................................................................. 21

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Solenoid Supply Monitoring .................................................................................................................................................. 21

Gear Ratio Monitoring ........................................................................................................................................................... 21
Torque Converter Monitoring ................................................................................................................................................ 22
Shift Energy Management ................................................................................................................................... 22
Pressure Modulation ............................................................................................................................................................. 22
Shift Map Selection.............................................................................................................................................. 22
Normal Mode......................................................................................................................................................................... 22
Uphill and Downhill Mode...................................................................................................................................................... 22
Altitude Mode ........................................................................................................................................................................ 22
Winter Mode.......................................................................................................................................................................... 22
Low Range Schedule ............................................................................................................................................................ 22
Warm up Schedule................................................................................................................................................................ 22
Hot Mode............................................................................................................................................................................... 23
Cruise.................................................................................................................................................................................... 23

2 Diagnosis and Testing .........................................................................................................................24

2.1 Wiring Diagram .................................................................................................................................................... 24
2.2 Wire Harness Connector Chart........................................................................................................................... 25
2.3 Unit Connector Description ................................................................................................................................ 25
Transmission Control Unit .................................................................................................................................. 25
Connector J1......................................................................................................................................................................... 25
Connector J2......................................................................................................................................................................... 25
Connector J3......................................................................................................................................................................... 25
Transmission........................................................................................................................................................ 26
Connector J4......................................................................................................................................................................... 26
Inhibitor Switch .................................................................................................................................................... 26
Connector J5......................................................................................................................................................................... 26
2.4 Trouble Code Diagnosis...................................................................................................................................... 27
Diagnostic Trouble Code List ............................................................................................................................. 27
Sub-System .......................................................................................................................................................... 29
TCU ....................................................................................................................................................................................... 29
Inhibitor Switch Assembly ..................................................................................................................................................... 31
Transmission Cooling............................................................................................................................................................ 33
Transmission Oil Temperature Sensor ................................................................................................................................. 34
Input Speed Sensor .............................................................................................................................................................. 37
Transmission Gear Select Lever........................................................................................................................................... 41
Output Speed Sensor............................................................................................................................................................ 44
Gear Engagement................................................................................................................................................................. 47
Torque Converter Control ..................................................................................................................................................... 49
Steering Wheel...................................................................................................................................................................... 50
Variable Bleed Solenoids ...................................................................................................................................................... 53
On/Off Solenoids................................................................................................................................................................... 60
CAN Network ........................................................................................................................................................................ 64
TCU Calibration..................................................................................................................................................................... 66

3 Maintenance Operations......................................................................................................................68
3.1 Stall Test ............................................................................................................................................................... 68
3.2 Transmission Reset Procedure (Replacement Transmission) ........................................................................ 68
Green Offset Reset .............................................................................................................................................. 68
Adaptive Reset ..................................................................................................................................................... 68
Green Offset Reset Procedure............................................................................................................................ 68
Adaptive Reset Procedure .................................................................................................................................. 68
3.3 Fluid Level Inspection ......................................................................................................................................... 69
3.4 Transmission Cooler and Hydraulic Line Flushing Procedure (New Transmission)..................................... 70

4 Lubrication ............................................................................................................................................71

5 Torque Specifications..........................................................................................................................72

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1 System Operation
1.1 General Description

The Model 78 six speed automatic transmission is available in two variants: four wheel drive and two wheel
drive.
The transmission has the following features:
Six forward speeds
One reverse gear
A torque converter with an integral converter lock-up clutch
Electronic shift and pressure controls
A single planetary gear-set
A double planetary gear-set
Two hydraulically controlled brake bands
Three multi-plate clutches
All hydraulic functions are directed by electronic solenoids to control:
Engagement feel
Shift feel
Shift scheduling
Modulated torque converter clutch applications
The transmission contains fully synthetic automatic transmission fluid (ATF) and is filled for life; therefore it
does not require periodic servicing.
Engine power reaches the transmission via a torque converter with integral converter lock-up clutch.
The six forward gears and one reverse gear are obtained from a single planetary set, followed by a double
planetary set. This type of gear-set arrangement is commonly known as Lepelletier type gear-set.
The Model 78 automatic transmission is electronically controlled. The control system is comprised of the
following elements:
External transmission control unit (TCU)
Internal embedded memory module (EMM)
Input and output speed sensors
Valve body unit comprised of four on/off solenoid valves and six variable bleed solenoids
Torque converter
Gear selection is achieved by the control of automatic transmission fluid (ATF) flow and pressure to operate
various internal clutches and bands. The TCU operates all the electrical components and provides for the
control of gear selection, shift pressure and torque converter slip control.
In the event of a system fault, the TCU also provides for failure mode effect control (FMEC) to maintain
maximum functional operation of the transmission. In the event of a total loss of control or electrical power,
the basic transmission functions (Park, Reverse, Neutral and Drive) are retained. The 4th gear ratio with the
torque converter clutch in the unlocked state is the retained gear state the hydraulic system supports without
any electrical assistance.
The transmission also contains an external P, R, N, D selector shaft position sensor (inhibitor switch) and an
internal transmission fluid temperature sensor.

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With manual mode applications, the TCU also requires information from the transmission gear selector
(TGS) shift knob to determine when the driver has initiated a manual gear selection. The TCU communicates
with other vehicle electronic control modules by the controller area network (CAN).
If a major fault develops, the transmission may automatically operate in a limp home (failure) mode to
enable the vehicle to be driven to an authorised dealer for repair. During limp home mode, the MIL indicator
on instrument cluster will be set and the transmission will operate with limited functionality. The level of
functionality is dependant on the fault detected. When in limp home mode, the transmission indicator light on
the instrument cluster will flash. Limp home mode may also be engaged if the battery charge falls below 8V.
If the transmission overheats, the shift patterns will automatically change to enable improved transmission
cooling. During transmission overheat, the instrument cluster transmission selector position display and the
over temperature condition is indicated by flashing the WINTER indicator on the instrument cluster until
normal transmission operating temperature is reached.
Under extreme over-temperature conditions, the transmission will disable all shifting and remain in a neutral
state until it has cooled to a safe level.
The TCU also provides for transmission diagnostics, which meet the requirements of OBD II legislation,
monitoring all components which may effect vehicle emissions. Additional diagnostic functions are also
supported to ensure fast repairs of all failures in the service environment.
In the event of a vehicle breakdown, the vehicle can be towed, providing the main driveshaft has been
removed prior to towing. Failure to do this will lead to a failed transmission due to insufficient lubrication to
transmission bearings.

1.2 Advanced Six Speed Features

Early Downshifts with Hard Braking and Skip Shifts

When heavy braking is detected, the transmission downshifts early and skips gears to provide increased
engine braking to provide gear selection for tip-in.

Gear Hold Going Uphill/Downhill

If the accelerator pedal is released when travelling uphill, upshifts are prevented to reduce busyness on
grades. If the accelerator pedal is released when travelling downhill, upshifts are prevented to enhance
engine braking.

Upshift Prevention with Fast-off Accelerator Pedal

Upshifts are prevented when the throttle is backed off very quickly to reduce busyness in sporty driving.

Drive and Reverse Engagement

A soft engagement feature avoids harsh take up of drive when selecting Drive or Reverse. This is achieved
by limiting engine speed and engine torque which results in a rapid, but progressive engagement of either
Drive or Reverse when moving from the Park or Neutral positions. Drive and Reverse engagements from
either Park or Neutral are performed in less than 2.2 seconds.
There is no drive engagement prevention strategy implemented on the transmission system as there is
sufficient engine strategy to protect the system. However, reverse engagement is prevented until engine
speed is less than 1400 rpm and the accelerator pedal position is less than 12% and vehicle speed is less
than 10 km/h.

Converter Clutch Lock-Up In All Gears

The transmission features converter clutch lock-up in all gears. This feature provides improved fuel economy
and vehicle performance. It also improves transmission cooling efficiency when towing heavy loads at low
speeds, e.g. in city driving or hill terrain.

Embedded Memory Module

The embedded memory module (EMM) is matched to the transmissions valve bodies during transmission
assembly to ensure refined shift quality. The EMM is integrated into the input speed sensor which is mounted
on the valve body in the transmission. The EMM is used to store data such as valve body calibration data
and valve body serial number.
Upon installation, the TCU will download the data from the EMM and utilise this data in the operation of the
transmission.

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1.3 Transmission Cooling

The transmission cooling system ensures rapid warm-up and constant operating temperature resulting in
reduced fuel consumption and refined shift quality.
It also includes a cooler by-pass within the hydraulic system to allow sufficient cooling and lubrication to the
transmission drivetrain in the event of a blockage in the transmission cooler.

1.4 Shift Strategy

Gear Change
Transmission gear change is controlled by the TCU. The TCU receives inputs from various engine and
vehicle sensors to select shift schedules and to control the shift feel and torque converter clutch (TCC)
operation at each gear change.

Coastdown
Coastdown downshifts occur at 0% pedal when the vehicle is coasting down to a stop.

Torque Demand
Torque demand downshifts occur (automatically) when the driver demand for torque is greater than the
engine can provide at that gear ratio. If applied, the transmission will disengage the TCC to provide added
acceleration.

Range Mode (Manual Mode)

This allows the driver to define the highest possible gear by selecting + or on the gear selector when the
lever is in the M position. When the lever is first moved to the manual M position the transmission will
select the lowest possible gear.
When maximum engine rpm is reached the transmission will upshift automatically regardless of the driver
selected limit. 4WD models with low range will not automatically upshift when low range is selected.

1st Gear State

The 1st gear state will display on the instrument cluster. Unlike the normal 1st gear, engine braking will be
available in this manual 1st state.

2nd Gear State

The 2nd gear state will display on the instrument cluster. 21 automatic kick-down shifts are available. 2nd
gear has engine braking available.

3rd Gear State

The 3rd gear state will display on the instrument cluster. 32 and 31 automatic kick-down shifts are available.
3rd gear has engine braking available.

4th Gear State

The 4th gear state will display on the instrument cluster. 43, 42 and 41 automatic kick-down shifts are
available. 4th gear has engine braking available.

5th Gear State

The 5th gear state will display on the instrument cluster. 54, 53 automatic kick-down shifts are available.
5th gear has engine braking available.

6th Gear State

The 6th gear state will display on the instrument cluster. 65, 64 automatic kick-down shifts are available.
6th gear has engine braking available.

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1.5 Transmission Components

2WD

4WD

Gear Train
Power is transmitted from the torque converter to the planetary gear-sets though the input shaft.
Clutches and bands are used to hold and drive certain combinations of gear states. This results in six
forward ratios and one reverse ratio, which are transmitted to the output shaft and differential/s.

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Single Planetary Gear-set

The single planetary gear-set overdrive carrier is driven by the input shaft.
The single planetary gear-set consists of:
One sun gear
Three planetary gears meshing with sun gear
One planetary gear carrier
One ring gear

Double Planetary

The double planetary gear-set is splined to the output shaft.

The double planetary gear-set consists of:
Two sun gears (forward and reverse)
Three short planetary gears meshing with sun gears
Three long planetary gears meshing with sun gears
One planetary gear carrier
One ring gear

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Clutches and Brake Bands

Other shift elements in addition to the torque

converter lock-up clutch are:
Three rotating multi-plate clutches C1, C2 & C3
Two brake bands (front and rear)
The multi-plate clutches are equalised in terms of
dynamic pressure. Its piston is exposed to the
transmission fluid flow on both sides in order to
prevent pressure build up in the clutch as the speed of
rotation increases. This pressure equalisation is
achieved by a piston dam. The advantages of this
dynamic pressure equalisation are:
Reliable clutch engagement and release in all
speed ranges
Improved shift refinement

Torque Converter

The torque converter contains a single plate lock-up clutch. The lock-up clutch can be controlled and
engaged in any forward gear. The clutch is applied by removing transmission fluid pressure from one side of
the plate and applying pressure to the other. The torque converter transmits and multiplies torque. The
torque converter is a three-element device consisting of:

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Impeller assembly
Turbine assembly
Stator assembly
The standard torque converter components operate as follows:
The impeller, which is driven by the engine, imparts a circular flow to the transmission fluid in the
converter.
This transmission fluid strikes the turbine wheel, which causes the flow to change its direction.
The transmission fluid flows out of the turbine wheel close to the hub and strikes the stator where its
direction is changed again to a direction suitable for re-entering the impeller.
The change in direction at the stator generates a torque reaction which increases the torque reaching
the turbine.
The ratio between turbine and impeller torque is referred to as torque multiplication or conversion.
The greater the difference in speed or rotation at the impeller and turbine, the greater the increase in
torque. The maximum increase is obtained when the turbine wheel is stationary. As turbine wheel
speed increases, the amount of torque multiplication gradually drops.
When the turbine wheel is rotating at about 85% of the impeller speed, torque conversion reverts to one,
that is to say torque at the turbine wheel is no higher than the torque at the impeller.
The stator, which is prevented from rotating backwards by a one-way clutch and the shaft in the
transmission housing, runs freely in the transmission fluid flow and overruns on the one-way clutch.
From this point on, the converter acts only as a fluid coupling. During the torque conversion process,
the stator ceases to rotate and bears against the housing by the one-way clutch.

Torque Converter Lock-up Clutch

The torque converter lock-up clutch is a device which
eliminates slip in the torque converter and therefore
helps to keep fuel consumption to a minimum.
The torque converter lock-up clutch includes a cooling
nozzle which allows for torque converter slip control.
This functionality allows for partial torque converter
lock-up at lower than normal engine rpm, which
improves fuel economy.
The torque converter lock-up clutch is engaged and
released via the control system.
Pressure at the torque converter lock-up clutch piston
is determined by an electronic variable bleed solenoid
(VBS).
The torque converter lock-up clutch can be controlled
and engaged in any forward gear.
When the torque converter lock-up clutch is released,
transmission fluid pressure behind the lock-up clutch
piston turbine area is equalised. The direction of flow
is through the turbine hub and the area behind the
piston into the turbine area.
To engage the torque converter lock-up clutch the
direction of transmission fluid flow is changed by a
valve in the transmission pump.
At the same time the space behind the torque converter lock-up clutch piston is vented. Fluid pressure
extends from the turbine area to the torque converter lock-up clutch piston and presses it against the cover
of the torque converter. This locks the turbine wheel between the piston and the cover and enables the drive
to pass with limited slip to the planetary gear train in normal operating conditions.

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Fluid Pump

The fluid pump is a parachoidal type pump delivering approximately 17.6 cc of transmission fluid per
revolution.
It is located between the torque converter and the transmission housing.
The torque converter is supported in the fluid pump by a plain bush bearing. The fluid pump is driven directly
from the engine by the torque converter cover and supplies transmission fluid directly to the valve body and
transmission.
The fluid pump draws in transmission fluid through a filter and delivers it at high pressure to the valve body.

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1.6 Hydraulic Schematics

Overall Hydraulic Circuit

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M78 Automatic Transmission Page14

Gear Fluid Flow Schematics

1st Gear Power Path Ratio 3.53:1

Manual 1st Gear Power Path Ratio 3.53:1

2nd Gear Power Path Ratio 2.14:1

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3rd Gear Power Path Ratio 1.48:1

4th Gear Power Path Ratio 1.16:1

5th Gear Power Path Ratio 0.87:1

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6th Gear Power Path Ratio 0.68:1

Reverse Gear Power Path Ratio 3.09:1

Neutral

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Park

1.7 Transmission Electronic Control System

The transmission control unit (TCU) and its input/output network control the following transmission
operations:
Shift timing
Line pressure
Clutch pressure (shift feel)
Torque converter clutch
In addition, the TCU receives input signals from certain transmission-related sensors and switches. The TCU
also uses these signals when determining transmission operating strategy.
Using all of these input signals, the TCU can determine when the time and conditions are right for a shift, or
when to apply or release the torque converter clutch. It will also determine the pressure needed to optimise
shift feel. To accomplish this, the TCU operates six variable bleed control solenoids and four on/off solenoids
to control transmission operation.
The following provides a brief description of each of the sensors and actuators used to control transmission
operation.

Transmission Control Unit

Caution: If the TCU requires reprogramming the handbrake must be firmly applied and the
transmission placed in Park (P).
The transmission control unit (TCU) is mounted under the left-hand front seat and controls the operation of
the transmission.
The TCU is activated and deactivated by the ignition power supply and is connected to the transmission link
harness by a 26 pin connector.
The TCU processes information received from internal sensors and signals received across the CAN bus in
analogue and digital forms such as:
Transmission input speed
Transmission output speed
Accelerator pedal position
Gear selector position
Engine torque
Engine speed
Transmission fluid temperature
Brake pedal status
Engine oil temperature
Engine coolant temperature
Ambient air temperature
Barometric pressure
This information is used by the TCU to decide which shift pattern to select and for shift energy management.
Electro-hydraulic solenoid valves and variable bleed solenoids control the transmission gear changes.
Six variable bleed solenoids and four on/off solenoids are used to direct transmission fluid flow to control the
fluid pressure within the three clutches and two bands. Separate pressure regulators are used exclusively for
torque converter clutch control and main transmission line pressure.

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The TCU monitors all TCU inputs and outputs to confirm correct system operation. If a fault occurs the TCU
is able to perform default action and inform the driver of the problem through the instrument cluster warning
lights. Detailed information is available via trouble codes which can be read with the service tool.

Communication Network

The TCU sends signals to be used by other vehicle systems via the CAN bus, such as:
Selector lever position
Selected gear state
Manual mode activation
Output torque
Input speed
Output speed
Transmission fluid temperature
Engine torque reduction requests

Embedded Memory Module

The embedded memory module (EMM) is matched to
the transmission valve body during manufacture.
The EMM is integrated into the input speed sensor
which is mounted on the valve body in the
transmission.
The EMM data contains transmission specific
characterisation information. Upon installation, the
TCU will upload the data from the EMM and utilise this
data in the operation of the transmission.

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Solenoid Valves and Variable Bleed Solenoids

The valve body contains four on/off solenoid valves and six variable bleed solenoids. The on/off solenoid
valves are actuated by the TCU and maintain two positions; open and closed. These valves are used to
switch the shift valves.
The variable bleed solenoids convert an electric current into a proportional hydraulic pressure. They are
energised by the TCU and supply variable pressure to each of the clutch or bands dedicated regulator valves.

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Sensor Inputs

Brake Pedal Position Switch

The brake pedal position (BPP) switch tells the TCU when the brakes are applied. The BPP is also used to
disengage the transmission gear selector (TGS) interlock when moving out of the Park position and as part
of the shifting strategy.

Engine Intake Temperature Sensor

The engine intake temperature (EIT) sensor detects intake air temperature and supplies the information to
the TCU.

Barometric Pressure Sensor

The barometric pressure (BARO) sensor detects the current air pressure and supplies the information to the
TCU.

Accelerator Pedal Position Sensor

The accelerator pedal position (APP) sensor is a potentiometer mounted on the accelerator pedal. The APP
sensor detects the position of the accelerator pedal and sends this information to the TCU. The APP sensor
signal is used for shift scheduling and TCC lock-up.

Input Shaft Speed Sensor

The input shaft speed (ISS) sensor is a hall effect type
sensor.
The ISS sensor is mounted internally in the
transmission and is located on the valve body.

Output Shaft Speed Sensor

The output shaft speed (OSS) sensor is a hall effect
type sensor.
The OSS sensor is mounted internally in the
transmission and is located at the rear of the
transmission main case.

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Transmission Fluid Temperature Sensor

The TCU utilises one transmission fluid temperature
sensor located in the valve body wiring loom. The
TCU uses the sensor input to activate various shift
strategies. The sensor is in the form of a temperature
dependant resistor.
The temperature sensor performs plausibility checks
on each sensor reading. If the inputs from the
temperature sensor are outside the working range it is
possible the sensor is either short or open circuit.

Inhibitor Switch
The TCU uses the position of this switch to determine
the position of the selector lever.
The selector lever is connected to the transmission via
a linkage mechanism which operates the transmission
selector shaft between positions Park, Reverse,
Neutral and Drive.
The inhibitor switch contains set resistances for each
position which are read by the TCU. The TCU uses
this information to control the shifts to reverse and
drive.
For models equipped with manual mode, the TCU
detects the drivers choice of manual range selection
(+ or -) by means of switches directly connected to the
selector lever and/or steering wheel.
Movement of the lever between Park, Reverse,
Neutral and Drive manually controls the flow of
transmission fluid, the TCU having control of the
forward gear selected in Drive.
If the lever is not in the Park or Neutral positions, or if
the switch is disconnected, starting of the engine is
inhibited.

Transmission Control Monitoring System

The TCU monitors all input and outputs to identify possible failures. If a fault is detected, the TCU takes the
appropriate action to ensure the transmission maintains a safe mode of operation, without sacrificing
transmission durability or driver safety.

Supply Monitoring
If the battery voltage is either too great or too low, the TCU will detect a fault condition.

Solenoid Supply Monitoring

While the solenoid operating transistors are being activated, checks are run for open circuits, shorts circuits
to ground and short circuits to supply. The monitoring function evaluates the voltage characteristics during
the switch ON process checking for the above faults.

Gear Ratio Monitoring

The gear ratio diagnostic checks if each gear ratio is correctly engaged. Also, following a gear shift the
diagnostic checks if the transmission has engaged the target gear within the allowed time.

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Torque Converter Monitoring

The TCU checks if the torque converter can be locked correctly. If torque converter lock-up does not occur
correctly the TCU performs the appropriate fail-safe action of opening the torque converter clutch.

Shift Energy Management

This function involves reducing or increasing the engine output torque during shifting. The aim when
upshifting is to reduce the energy which is dissipated in the friction elements of the transmission. This is
done by reducing the engine torque during the ratio change without interrupting the tractive drive. This
function is used for:
Increasing the transmission service life by shortening the slipping time
Improving the shift comfort by reducing the step change in torque caused by the gearshift
Transferring a higher engine power, this is allowed by the mechanical in-gear strength of the
transmission
Real-time control of engine torque is required to maintain maximum shift quality and transmission durability.
The TCU has the ability to control the engine torque during the gearshift to synchronise with the operation of
the transmission clutches.

Pressure Modulation
To provide a high level of shift comfort and durability, the hydraulic pressure in the shift related friction
elements of the transmission must be matched accurately to the transmission input torque. This hydraulic
pressure is composed of a hydraulically pre-set basic pressure and a controlling pressure which is set by one
of the variable bleed solenoids.
The transmission input torque can be directly calculated from the following operating parameters: engine
torque signals, engine speed or any signals transmitted from the engine management ECU by CAN, and
converter slip. Separate pressure characteristics for each gear change make it possible to adapt precisely to
the particular shift operation.
High and Low range operation has different parameters to optimise shift quality.

Shift Map Selection

The driver can manually select between normal (S) and winter modes (W) via the mode switch. Depending
on the transmission temperature, uphill and downhill grades and altitude, shift maps will be selected by the
TCU to suit the driving conditions. The following maps are available.

Normal Mode
Normal Mode is selected when the lever is in the D position with the mode switch in the normal (S) position
and the transmission is within normal temperature ranges. Shift schedule points are optimised for fuel
efficiency and general driving conditions.

Uphill and Downhill Mode

In this mode, depending on the load of the vehicle, adaptive shift maps are selected to progressively adjust
the shift points and torque converter lock points.

Altitude Mode
Shift points are automatically adjusted at higher altitudes to compensate for changes in engine torque where
the torque produced by the engine is greatly reduced by the effects of reduced barometric pressure and
temperature.

Winter Mode
When winter mode is selected, starting in second gear is facilitated and the WINTER mode indicator light is
switched ON. To prevent wheel spin on slippery surfaces, the transmission will not allow first gear unless
manually overridden.

Low Range Schedule

When the transfer case is in 4L position, the transmission uses a different shift map to optimise low range
st
driving. Similar to winter mode, 1 gear is inhibited. The transmission may skip gears, e.g. 24, to optimise
engine rpm.

Warm up Schedule
Used typically when transmission fluid temperature is below 20C.
The torque converter will not lock-up below 20C to assist in transmission warm-up.

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Hot Mode
The hot mode is progressively applied between temperatures of 110 145C. The torque converter lock-up
is increased to prevent heat generation by the torque converter.
As additional assistance to the hot mode, the following are activated:
Above 110C the electrical radiator fans are switch ON
Above 130C the engine torque will be reduced and the WINTER light on the instrument cluster will
flash
Above 145C the transmission will neutralise until the fluid temperature falls below 120C as a final
protection.
Activation of the hot mode inhibits other transmission performance features including uphill and downhill
compensation and altitude compensation. Some degradation in shift feel may be experienced as the torque
converter is not unlocked during shifting. The fluid temperature must be below 105C to exit all hot modes.

Cruise
When cruise control is activated the engine ECU may request the transmission to downshift under trailing
throttle conditions to increase engine braking.

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2 Diagnosis and Testing

2.1 Wiring Diagram

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2.2 Wire Harness Connector Chart

2.3 Unit Connector Description

Transmission Control Unit

Connector J1
Terminal / Pin Function Terminal / Pin Function
J11 VBS Solenoid 9 J19 On / Off Solenoid 2
J12 VBS Solenoid 10 J110 On / Off Solenoid 1
J13 VBS Solenoid 7 J111 On / Off Solenoid 4
J14 VBS Solenoid 8 J112 On / Off Solenoid 3
J15 VBS Solenoid 5 J113
J16 VBS Solenoid 6 J114
J17 VBS Solenoid Return J115 On / Off Solenoid Return
J18 Ground J116 Ignition Supply Voltage

Connector J2
Terminal / Pin Function Terminal / Pin Function
J21 CAN High J27 CAN Low
J22 J28
J23 J29 Steering Wheel Range Control
J24 Transmission Gear Selector Range Control J210 Range Active
J25 J211
J26 J212

Connector J3
Terminal / Pin Function Terminal / Pin Function
J31 Output Speed J311
J32 EMM / Speed Sensor Supply Voltage J312 EMM / Speed Sensor Ground
J33 Input Speed J313
J34 Embedded Memory Module Data J314 Embedded Memory Module Clock

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J35 J315 Switch Ground

J36 Mode J316
J37 Gear Lever J317 Gear Lever Ground
J38 Transmission Fluid Temperature J318 Transmission Fluid Temperature Return
J39 J319
J310 J320

Transmission

Connector J4
Terminal / Pin Function Terminal / Pin Function
J41 VBS Solenoid Return J414
J42 VBS Solenoid 5 J415
J43 VBS Solenoid 6 J416
J44 VBS Solenoid 7 J417
J45 VBS Solenoid 8 J418
J46 VBS Solenoid 9 J419
J47 VBS Solenoid 10 J420 On/Off Solenoid Return
J48 EMM Data / Speed Sensor Ground J421 On/Off Solenoid
J49 EMM / Speed Sensor Supply Voltage J422 On/Off Solenoid
J410 Output Speed J423 On/Off Solenoid
J411 Input Speed J424 On/Off Solenoid
J412 Embedded Memory Module Data J425 Transmission Fluid Temperature Return
J413 Embedded Memory Module Clock J426 Transmission Fluid Temperature Input

Inhibitor Switch

Connector J5
Terminal / Pin Function Terminal / Pin Function
J51 Reverse Circuit J54 Gear Lever Ground
J52 Starter Circuit J55 Gear Lever
J53 Starter Circuit J56 Reverse Circuit

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2.4 Trouble Code Diagnosis

Diagnostic Trouble Code List

DTC Description Sub System
P0603 TCU Adaptive Data Memory Error
TCU (see page 29)
P0604 TCU Adaptive Data Limit Reached

P0707 Gear Lever Position Sensor Error Low

Inhibitor Switch Assembly (see page 31)
P0708 Gear Lever Position Sensor Error High

P0711 Transmission Oil Temp Over Temp Transmission Cooling (see page 33)

P0712 Transmission Oil Temperature Sensor Error Low

Transmission Oil Temperature Sensor
Transmission Oil Temperature Sensor Error High (Open (see page 34)
P0713
Circuit)

P0716 Input Shaft/Turbine Speed Value

Input Speed Sensor (see page 37)
P0717 Input Shaft/Turbine Speed Sensor Erratic

P071D Manual Shift Control Up/Down (TGS) Switch Stuck

Transmission Gear Select (TGS) Lever
P071E Manual Shift Control Up/Down (TGS) Switch Signal Low
(see page 41)
P071F Manual Shift Control Up/Down (TGS) Switch Signal High

P0721 Output Shaft Speed Sensor Value

Output Speed Sensor (see page 44)
P0722 Output Shaft Speed Sensor Erratic

P0729 Gear 6 Incorrect Ratio

P0731 Gear 1 or M1 Incorrect Ratio

P0732 Gear 2 Incorrect Ratio

P0733 Gear 3 Incorrect Ratio Gear Engagement (see page 47)

P0734 Gear 4 Incorrect Ratio

P0735 Gear 5 Incorrect Ratio

P0736 Reverse Incorrect Ratio

P0741 Torque converter clutch circuit stuck off

P0742 Torque converter clutch circuit stuck on Torque Converter Control (see page 49)

P0744 Torque converter clutch Slip Error

Manual Shift Control Up/Down (Steering Wheel) Switch

P0826
Stuck

Manual Shift Control Up/Down (Steering Wheel) Switch

P0827 Steering Wheel (see page 50)
Signal Low

Manual Shift Control Up/Down (Steering Wheel) Switch

P0828
Signal High

P0962 Solenoid S9 Over Current

P0963 Solenoid S9 Low Current

Variable Bleed Solenoids (see page 53)
P0966 Solenoid S10 Over Current

P0967 Solenoid S10 Low Current

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DTC Description Sub System

P0973 Solenoid S1 Over Current

P0974 Solenoid S1 Low Current

P0976 Solenoid S2 Over Current

P0977 Solenoid S2 Low Current

ON / OFF Solenoids (see page 60)
P0979 Solenoid S3 Over Current

P0980 Solenoid S3 Low Current

P0982 Solenoid S4 Over Current

P0983 Solenoid S4 Low Current

P0985 Solenoid S5 Over Current

P0986 Solenoid S5 Low Current

P0998 Solenoid S6 Over Current

P0999 Solenoid S6 Low Current

Variable Bleed Solenoids (see page 53)
P099B Solenoid S7 Over Current

P099C Solenoid S7 Low Current

P099E Solenoid S8 Over Current

P099F Solenoid S8 Low Current

P1604 TCU EMM Data Error TCU (see page 29)

P1605 EMM Data Mismatch

P1610 EMM Comms Error Input Speed Sensor (see page 37)

P1611 EMM Data Error

P1701 TCU Supply Voltage Low

TCU (see page 29)
P1703 TCU Supply Voltage High

Cyclic CAN messages from Engine Management ECU are

U0100
unavailable

Cyclic CAN messages from Transfer Case ECU are

U0102
unavailable

Cyclic CAN messages from Brake System ECU

U0121
(ABS/ESP/TCS) are unavailable

U0401 CAN signals from EMS are out of range or Invalid

U0403 CAN signals from Transfer Case are out of range or Invalid
CAN Network (see page 64)
CAN signals from Brake System ECU (ABS/ESP/TCS) are
U0415
out of range or Invalid

U1601 TCU Application Software Missing or Corrupted

U1606 TCU Calibration Error - Platform

U1607 TCU Calibration Error - Active Variant

U1608 TCU VIN Coding Error

U1609 TCU Hardware (pcb) Calibration Error

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Sub-System

TCU
The transmission control unit (TCU) controls transmission gear selection via variable bleed solenoids and On/Off
solenoids. The TCU operating voltage is 8-16 V, with current draw typically being less than 4 amps but reaching as high
as 10 amps during gear shifts.
As the mechanical components of the transmission change due to wear etc, the TCU adapts its shift data to
accommodate these changes and maintain shift quality over the life of the vehicle. If a transmission component degrades
to a point whereby the TCU is unable to adapt its shift data to maintain shift quality, the TCU will set a DTC.

DTC Title System Action

P0603 TCU Adaptive Data Memory Error Normal transmission operation with
degraded shift quality

P0604 TCU Adaptive Data Limit Reached Normal transmission operation with
degraded shift quality
TCU SENDS MIL REQUEST ON
P1604 TCU EMM Data Error
Transmission in LHM
TCU SENDS MIL REQUEST ON
P1701 TCU Supply Voltage Low
Transmission in LHM
TCU SENDS MIL REQUEST ON
P1703 TCU Supply Voltage High
Transmission in LHM

DTC Description
DTC Description
P0603 TCU is not able to store adaptive (learning) data.

TCU shift adaptation is applying maximum effort. This may be because the transmission operation has
P0604
degraded significantly.

P1604 The EMM Data image stored in the TCU is corrupted or missing.

P1701 The battery voltage sensor is reporting a value too low to operate the solenoids correctly.

The battery voltage sensor is reporting a value too high for continuous operation of solenoids. The
P1703
solenoids will be disabled and the transmission in LHM during this condition.

Schematic

Connector Details

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DTC Details
DTC Evaluation Conditions Possible Causes Actions
P0603 Ignition key in ON position TCU Hardware Failure Clear DTC and
TCU Adaptive Data check if DTC sets
Memory Error within the evaluation
conditions
Replace TCU
P0604 Ignition key in ON position Transmission Clear DTC and
TCU Adaptive Data check if DTC sets
Limit Reached within the evaluation
conditions
Service
transmission
P1604 Ignition key in ON position TCU has never Clear DTC and
TCU EMM Data Error been powered with check if DTC sets
valid EMM within the evaluation
connected. conditions
TCU hardware Check for EMM
failure. related DTC.
Replace TCU
P1701 Ignition key in ON position Vehicle charging Clear DTC and
TCU Supply Voltage Engine speed >300 rpm system check if DTC sets
Low Vehicle battery within the evaluation
TCU supply voltage <8 V for conditions
0.5 seconds TCU to
Transmission Check vehicle
harness and/or charging system
connector fault Check vehicle
TCU battery
Check circuit
between terminal
J1-8 and vehicle
ground
Check circuit
between terminal
J1-16 and ignition
source. Refer to
vehicle electrical
section for circuit
specific information
Check supply
voltage at TCU
Replace TCU
P1703 Ignition key in ON position Vehicle charging Clear DTC and
TCU Supply Voltage TCU supply voltage >17 V for 60 system check if DTC sets
High seconds Vehicle battery within the evaluation
conditions
TCU to
Transmission Check vehicle
harness and/or charging system
connector fault Check vehicle
TCU battery
Check circuit
between terminal
J1-8 and vehicle
ground
Check circuit
between terminal
J1-16 and ignition
source. Refer to
vehicle electrical
section for circuit
specific information
Check supply
voltage at TCU
Replace TCU

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DTC Clearing
DTC Conditions
P0603, P0604, Ignition ON
P1604, P1701 &
Engine stopped
P1703
Scan tool

Inhibitor Switch Assembly

The inhibitor switch assembly provides gear position data to the transmission control unit (TCU), inhibits starter motor
operation when the transmission gear select (TGS) lever is not in the neutral or park position, and enables reverse light
operation when the TGS lever is in the reverse position. The inhibitor switch has an individual circuit for each of these
functions, with only the gear lever position circuit being connected directly to the TCU.
The TCU supplies a 5 V reference signal to the gear lever position circuit (inhibitor switch) and measures the voltage
drop in the circuit to determine the gear lever position. There is a different resistance value for each position of the TGS
lever.

DTC Title System Action

TCU SENDS MIL REQUEST ON
P0707 Gear Lever Position Sensor Error Low
Transmission in LHM
TCU SENDS MIL REQUEST ON
P0708 Gear Lever Position Sensor Error High
Transmission in LHM

Description
DTC Description
P0707 The Gear Lever Position sensor (Inhibitor Switch) is giving a value indicative of a short circuit to ground

P0708 The Gear Lever Position sensor (Inhibitor Switch) is giving a value indicative of an open circuit

Schematic

Connector Details

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Resistance Values

DTC Details
DTC Evaluation Conditions Possible Causes Actions
P0707 Ignition key in ON position TCU to Inhibitor Clear DTC and
Gear Lever Position Switch Assy check if DTC sets
Sensor Error Low harness and/or within the evaluation
connector fault conditions
Inhibitor Switch Disconnect
Assy connector J5 from
TCU the inhibitor switch
assembly. Check
resistance of
inhibitor switch
assembly between
terminals 4 and 5 for
each position of
TGS lever. Refer to
the resistance table
above for
specifications.
Replace
transmission if the
resistance values
are outside of the
specified range.
Check circuit
between terminals
J5-4 and
J3-17 for short or
open condition
Check circuit
between terminals
J5-5 and J3-7 for
short or open
condition
Disconnect
connector J5 from
inhibitor switch
assembly and
measure voltage
across J5-4 and J5-
5 with the ignition
key in the ON
position. Voltage
reading should be 5
V 0.1 V. If voltage
reading is outside
specifications,
replace TCU

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DTC Evaluation Conditions Possible Causes Actions

P0708 Ignition key in ON position TCU to Inhibitor Clear DTC and
Gear Lever Position Switch Assy check if DTC sets
Sensor Error High harness and/or within the evaluation
connector fault conditions
Inhibitor Switch Disconnect
Assy connector J5 from
TCU the inhibitor switch
assembly. Check
resistance of
inhibitor switch
assembly between
terminals 4 and 5 for
each position of
TGS. Refer to the
resistance table
above. Replace
transmission
assembly if the
resistance values
are outside of the
specified range.
Check circuit
between terminals
J5-4 and
J3-17 for short or
open condition
Check circuit
between terminals
J5-5 and J3-7 for
short or open
condition
Replace TCU

DTC Clearing
DTC Conditions
P0707 & P0708 Ignition ON
Engine stopped
Scan tool

Transmission Cooling
The transmission control unit (TCU) monitors the transmission oil temperature. If the vehicle cooling system is unable to
maintain a satisfactory transmission oil temperature the TCU will take precautionary measures to prevent damage to the
transmission and other vehicle components.
The TCU also monitors the rate of temperature change according to current operating conditions (performance). If the
temperature sensor performance is outside a pre-determined set of values, DTC P0711 will set.

DTC Title System Action

P0711 Transmission Oil Temp Over Temp Normal transmission operation with
degraded shift quality and WINTER
indicator flashing when transmission oil
temperature is >130C.
When the transmission oil temperature
is >145C the TCU will disable gear
engagement until transmission oil
temperature is <120C

DTC Description
DTC Description
P0711 Transmission Oil Temperature is high enough to cause degraded transmission operation

DTC Details
DTC Evaluation Conditions Possible Causes Actions
P0711 Ignition key in ON position Transmission cooler Clear DTC and
Transmission Oil Transmission oil blocked check if DTC sets
Temp Over Temp Transmission cooler within the evaluation

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temperature is >130C lines restricted conditions

Engine cooling Inspect transmission
system fault oil level and oil
quality
Inspect transmission
cooling system
Inspect engine
cooling system

DTC Clearing
DTC Conditions
P0711 Ignition ON
Engine stopped
Scan Tool

Transmission Oil Temperature Sensor

The automatic transmission fluid temperature (TFT) sensor is mounted in the valve body harness tray. The TFT sensor is
a negative coefficient thermistor.
The transmission control unit (TCU) supplies a 5 V reference signal to the sensor and measures the voltage drop in the
circuit. When the transmission fluid is cold, the sensor resistance is high, with the sensor resistance decreasing as the
fluid temperature increases.

DTC Title System Action

P0712 Transmission Oil Temperature Sensor Error Low TCU SENDS MIL REQUEST ON

P0713 Transmission Oil Temperature Sensor Error High TCU SENDS MIL REQUEST ON

DTC Description
DTC Description
P0712 Transmission oil temperature sensor is giving a value indicative of a short circuit to ground.

P0713 Transmission oil temperature sensor is giving a value indicative of an open circuit.

Schematic

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Connector Details

Resistance Values

DTC Details
DTC Evaluation Conditions Possible Causes Actions
P0712 Ignition key in ON position TCU to Clear DTC and
Transmission Oil Transmission check if DTC sets
Temperature Sensor harness and/or within the evaluation
Error Low connector fault conditions
Transmission Check circuit
internal harness between terminals
and/or connector J3-8 and
fault J4-26 for short
Temperature condition

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DTC Evaluation Conditions Possible Causes Actions

sensor. Check circuit
TCU between terminals
J3-18 and J4-25 for
short condition
Disconnect
transmission
connector J4. Check
resistance of
transmission oil
temp. sensor
between terminals
J4-25 and J4-26.
Refer to the
resistance table
above for
specifications.
Replace
transmission
assembly if the
resistance values
are outside of the
specified range
Disconnect
connector J3 from
the TCU and
measure voltage
across TCU
terminals (TCU side)
J3-8 and J3-18 with
the ignition key in
the ON position.
Voltage reading
should be 5 V 0.1
V. If voltage reading
is outside
specifications,
replace TCU
P0713 Ignition key in ON position TCU to Clear DTC and
Transmission Oil Transmission check if DTC sets
Temperature Sensor harness and/or within the evaluation
Error High connector fault conditions
Transmission Check circuit
internal harness between terminals
and/or connector J3-8 and
fault J4-26 for open
Temperature sensor condition

TCU Check circuit

between terminals
J3-18 and J4-25 for
open condition
Disconnect
transmission
connector J4. Check
resistance of
transmission oil
temp. sensor
between terminals
J4-25 and J4-26.
Refer to the
resistance table
above for
specifications.
Replace
transmission
assembly if the
resistance values
are outside of the
specified range
Disconnect
connector J3 from
the TCU and
measure voltage
across TCU
terminals (TCU side)
J3-8 and J3-18 with

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DTC Evaluation Conditions Possible Causes Actions

the ignition key in
the ON position.
Voltage reading
should be 5 V 0.1
V. If voltage reading
is outside
specifications,
replace TCU

DTC Clearing
DTC Conditions
P0712 & P0713 Ignition ON
Engine stopped
Scan tool

Input Speed Sensor

The ISS sensor is a Hall Effect type sensor and is mounted on the valve body in the transmission.
The EMM is matched to the transmission valve body during manufacture. The EMM is integrated into the input speed
sensor.
The hall effect sensor drives the signal low. The TCU then pulls the signal up to 5 V via a resistor, 36 times per revolution
of the C2 cylinder.

DTC Title System Action

TCU SENDS MIL REQUEST ON
Closed loop torque converter clutch slip
control is disabled
P0716 Input Shaft/Turbine Speed Value
Adaptive learning is disabled
Engine speed is used to estimate input shaft
speed for gear shifting
TCU SENDS MIL REQUEST ON
Closed loop torque converter clutch slip
control is disabled
P0717 Input Shaft/Turbine Speed Sensor Erratic
Adaptive learning is disabled
Engine speed is used to estimate input shaft
speed for gear shifting

P1605 EMM Data Mismatch Transmission in LHM

P1610 EMM Comms Error None

TCU SENDS MIL REQUEST ON
P1611 EMM Data Error Last known valid EMM data in TCU used
Normal transmission operation

Description
DTC Description
P0716 The input shaft speed (ISS) is compared to engine speed and validated for plausibility

P0717 The input speed sensor is receiving intermittent or spurious pulses.

The Embedded Memory Module (EMM) data stored in the TCU does not match the EMM module in the
P1605
transmission

P1610 The TCU was unable to communicate with EMM

P1611 The data stored in the EMM is corrupted or missing or invalid

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Schematic

Connector Details

Speed sensor is receiving intermittent or spurious pulses.

DTC
P0712
P0717
P0722

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DTC Details
DTC Evaluation Conditions Possible Causes Actions
P0716 Ignition key in ON position TCU to Clear DTC and
Input Shaft/Turbine Engine speed >3000 rpm Transmission check if DTC sets
Speed Value harness and/or within the evaluation
connector fault conditions
Transmission Check circuit
internal harness between terminals
and/or connector J3-3 and J4-11 for
fault short or open
Input speed sensor condition

TCU Check circuit

between terminals
J3-2 and J4-9 for
short or open
condition
Check circuit
between terminals
J3-12 and J4-8 for
short or open
Disconnect
transmission
connector J4.
Measure the voltage
across terminals J4-
8 and J4-9 with
ignition key in ON
position. Voltage
reading should be
>10 V. Replace the
TCU if the reading is
<10 V
Measure the voltage
across terminals J4-
8 and J4-11 with
ignition key in ON
position. Voltage
reading should be 5
V 0.1 V .Replace
the TCU if the
reading is not within
specification
Reconnect
transmission
connector J4.
Connect an
oscilloscope to J3-3
and J3-12 and start
the engine. Increase
engine rpm and
observe the square
wave pattern. If the
pattern shows
switching from 5 V
to 0 V, replace the
TCU. If the pattern
does not show
switching, replace
the transmission

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DTC Evaluation Conditions Possible Causes Actions

P0717 Ignition key in ON position TCU to Clear DTC and
Input Shaft/Turbine Engine speed is >3000 rpm Transmission check if DTC sets
Speed Sensor Erratic harness and/or within the evaluation
connector fault conditions
Transmission Check circuit
internal harness between terminals
and/or connector J3-3 and J4-11 for
fault short or open
Input speed sensor condition

TCU Check circuit

between terminals
J3-2 and J4-9 for
short or open
condition
Check circuit
between terminals
J3-12 and J4-8 for
short or open
Disconnect
transmission
connector J4.
Measure the voltage
across terminals J4-
8 and J4-9 with
ignition key in ON
position. Voltage
reading should be
>10 V. Replace the
TCU if the reading is
<10 V
Measure the voltage
across terminals J4-
8 and J4-11 with
ignition key in ON
position. Voltage
reading should be 5
V 0.1 V .Replace
the TCU if the
reading is not within
specification
Reconnect
transmission
connector J4.
Connect an
oscilloscope to J3-3
and J3-12 and start
the engine. Increase
engine rpm and
observe the square
wave pattern. If the
pattern shows
switching from 5 V
to 0 V, replace the
TCU. If the pattern
does not show
switching, replace
the transmission
P1605 Ignition key in ON position EMM data stored in the TCU Clear DTC and
EMM Data Mismatch does not match the EMM check if DTC sets
module in the transmission. within the evaluation
This indicates that the conditions
transmission or TCU has been
Perform diagnostic
replaced.
reset procedure.
(see Transmission
Reset Procedure
(Replacement
Transmission) page
68)

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DTC Evaluation Conditions Possible Causes Actions

P1610 Ignition key in ON position TCU to Clear DTC and
EMM Comms Error Transmission check if DTC sets
harness and/or within the evaluation
connector fault conditions
Transmission Check circuit
internal harness between terminals
and/or connector J3-2 and J4-9 for
fault short or open
Input Shaft Speed condition
Sensor Check circuit
TCU between terminals
J3-12 and J4-8 for
short or open
Check circuit
between terminals
J3-4 and J4-12 for
short or open
condition
Check circuit
between terminals
J3-14 and J4-13 for
short or open
condition
Replace the
transmission
P1611 Ignition key in ON position Input Shaft Speed Clear DTC and
EMM Data Error Sensor check if DTC sets
within the evaluation
conditions
Replace the
transmission

DTC Clearing
DTC Conditions
P0716, P0717, Ignition ON
P1605, P1610 &
Engine stopped
P1611
Scan tool

Transmission Gear Select Lever

The transmission gear select lever contains the mode switch, manual mode active switch and up/down switches. These
switches are connected directly to the TCU.

DTC Title System Action

Manual shift control (TGS) switches
P071D Manual Shift Control Up/Down (TGS) Switch Stuck
disabled
Manual shift control (TGS) switches
P071E Manual Shift Control Up/Down (TGS) Switch Signal Low
disabled
Manual shift control (TGS) switches
P071F Manual Shift Control Up/Down (TGS) Switch Signal High
disabled

Description
DTC Description
The Manual Shift Control Up/Down switch (TGS) has been depressed for more than 120 seconds
DTC P071D
continuously. This may indicate a faulty switch

DTC P071E The Manual Shift Control Up/Down (TGS) switch signal is giving a value indicative of a short circuit

DTC P071F The Manual Shift Control Up/Down (TGS) switch signal is giving a value indicative of an open circuit

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Schematic

Connector Details

Resistance Values

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DTC Details
DTC Evaluation Conditions Possible Causes Actions
P071D Ignition key in ON position Shift Control Clear DTC and
Manual Shift Control Up/Down switch check if DTC sets
Up/Down (TGS) (TGS) within the evaluation
Switch Stuck TCU to Shift Control conditions
Up/Down switch Check up/down
harness and/or switch (TGS)
connector fault mechanical
TCU operation
Disconnect TCU
connectors J2 & J3
and measure
resistance across
terminals J2-4 and
J3-15. Refer to the
resistance table
above for
specifications.
Replace TGS lever if
the resistance
values are outside of
the specified range
Replace TCU
P071E Ignition key in ON position Shift Control Clear DTC and
Manual Shift Control Up/Down switch check if DTC sets
Up/Down (TGS) (TGS) within the evaluation
Switch Signal Low TCU to Shift Control conditions
Up/Down switch Check up/down
harness and/or switch (TGS)
connector fault mechanical
TCU operation
Check circuit
between terminal J2-
4 and Shift Control
Up/Down switch
(TGS) for short or
open condition
Check circuit
between terminals
J3-15 and TGS
Lever for short or
open condition
Disconnect TCU
connectors J2 & J3
and measure
resistance across
terminals J2-4 and
J3-15. Refer to the
resistance table
above for
specifications.
Replace TGS lever if
the resistance
values are outside of
the specified range
Replace TCU

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DTC Evaluation Conditions Possible Causes Actions

P071F Ignition key in ON position Shift Control Clear DTC and
Manual Shift Control Up/Down switch check if DTC sets
Up/Down (TGS) (TGS) within the evaluation
Switch Signal High TCU to Shift Control conditions
Up/Down switch Check up/down
harness and/or switch (TGS)
connector fault mechanical
TCU operation
Check circuit
between terminal J2-
4 and Shift Control
Up/Down switch
(TGS) for short or
open condition
Check circuit
between terminals
J3-15 and TGS
Lever for short or
open condition
Disconnect TCU
connectors J2 & J3
and measure
resistance across
terminals J2-4 and
J3-15. Refer to the
resistance table
above for
specifications.
Replace TGS lever if
the resistance
values are outside of
the specified range
Replace TCU

DTC Clearing
DTC Conditions
P071D, P071E, Ignition ON
P071F
Engine stopped
Scan tool

Output Speed Sensor

The OSS sensor is a Hall Effect type sensor and is mounted at the rear of the transmission main case.
The hall effect sensor drives the signal low. The TCU then pulls the signal up to 5 V via a resistor, 22 times per revolution
of the transmission output shaft.

DTC Title System Action

TCU SENDS MIL REQUEST ON
P0721 Output Shaft Speed Sensor Value
Transmission in LHM
TCU SENDS MIL REQUEST ON
P0722 Output Shaft Speed Sensor Erratic
Transmission in LHM

Description
DTC Description
The output shaft speed (OSS) sensor is compared to external equivalent speed signals and validated for
P0721
integrity

P0722 The output speed sensor is receiving intermittent or spurious pulses.

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Schematic

Connector Details

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DTC Details
DTC Evaluation Conditions Possible Causes Actions
P0721 Ignition key in ON position TCU to Clear DTC and
Output Shaft Speed Transmission check if DTC sets
Sensor Value harness and/or within the evaluation
connector fault conditions
Transmission Check circuit
internal harness between terminals
and/or connector J3-1 and J4-10 for
fault short or open
Output speed condition
sensor Check circuit
TCU between terminals
J3-2 and J4-9 for
short or open
condition
Check circuit
between terminals
J3-12 and J4-8 for
short or open
Disconnect
connector J4 from
transmission and
measure voltage
across terminals J4-
8 and J4-9. If
reading is not >10 V,
replace TCU
Measure voltage
across terminals J4-
8 and J4-10. If
reading is not 5 V
0.1 V, replace TCU
Connect connector
J4 to transmission,
start engine, and
connect
oscilloscope to
terminal J3-3. Shift
TGS to Park
position, increase
engine speed and
observe square
wave switching from
5 V to 0 V. If correct,
replace TCU. If not,
replace transmission

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M78 Automatic Transmission Page47

DTC Evaluation Conditions Possible Causes Actions

P0722 Ignition key in ON position TCU to Clear DTC and
Transmission check if DTC sets
Output Shaft Speed
harness and/or within the evaluation
Sensor Erratic
connector fault conditions
Transmission Check circuit
internal harness between terminals
and/or connector J3-1 and J4-10 for
fault short or open
Output speed condition
sensor Check circuit
TCU between terminals
J3-2 and J4-9 for
short or open
condition
Check circuit
between terminals
J3-12 and J4-8 for
short or open
Disconnect
connector J4 from
transmission and
measure voltage
across terminals J4-
8 and J4-9. If
reading is not >10 V,
replace TCU
Measure voltage
across terminals J4-
8 and J4-10. If
reading is not 5 V
0.1 V, replace TCU
Connect connector
J4 to transmission,
start engine, and
connect
oscilloscope to
terminal J3-3. Shift
TGS to Park
position, increase
engine speed and
observe square
wave switching from
5 V to 0 V. If correct,
replace TCU. If not,
replace
transmission.

DTC Clearing
DTC Conditions
P0721 & P0722 Ignition ON
Engine stopped
Scan tool

Gear Engagement
Transmission gear change is controlled by the TCU. The TCU receives inputs from various engine and
vehicle sensors to select shift schedules and to control the shift feel and torque converter clutch (TCC)
operation at each gear change.

DTC Title System Action

TCU SENDS MIL REQUEST ON
P0729 Gear 6 Incorrect Ratio
Transmission in LHM
TCU SENDS MIL REQUEST ON
P0731 Gear 1 or M1 Incorrect Ratio
Transmission in LHM
TCU SENDS MIL REQUEST ON
P0732 Gear 2 Incorrect Ratio
Transmission in LHM

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M78 Automatic Transmission Page48

DTC Title System Action

TCU SENDS MIL REQUEST ON
P0733 Gear 3 Incorrect Ratio
Transmission in LHM
TCU SENDS MIL REQUEST ON
P0734 Gear 4 Incorrect Ratio
Transmission in LHM
TCU SENDS MIL REQUEST ON
P0735 Gear 5 Incorrect Ratio
Transmission in LHM
TCU SENDS MIL REQUEST ON
P0736 Reverse Incorrect Ratio
Transmission in LHM

Description
DTC Description
The observed gear ratio in GEAR 6 when not shifting is outside nominal values +/-10% for more than 0.5
P0729
seconds.
The observed gear ratio in GEAR 1 or GEAR MANUAL 1 when not shifting is outside nominal values +/-
P0731
10% for more than 0.5 seconds.
The observed gear ratio in GEAR 2 when not shifting is outside nominal values +/-10% for more than 0.5
P0732
seconds.
The observed gear ratio in GEAR 3 when not shifting is outside nominal values +/-10% for more than 0.5
P0733
seconds.
The observed gear ratio in GEAR 4 when not shifting is outside nominal values +/-10% for more than 0.5
P0734
seconds.
The observed gear ratio in GEAR 5 when not shifting is outside nominal values +/-10% for more than 0.5
P0735
seconds.
The observed gear ratio in REVERSE when not shifting is outside nominal values +/-10% for more than 0.5
P0736
seconds.

DTC Details
DTC Evaluation Conditions Possible Causes Actions
P0729 Ignition key in ON position Low oil level Clear DTC and
The observed gear Engine speed >300 rpm Contaminated oil check if DTC sets
ratio in GEAR 6 is within the evaluation
Engine not in LHM Mechanical damage conditions
incorrect
Transmission oil temperature TCU Check oil level
>0C
Check oil quality
Transmission output shaft
speed >300 rpm Check for
mechanical damage
Transmission gear select
lever NOT in Neutral or Park Replace
transmission
P0731 Ignition key in ON position Low oil level Clear DTC and
The observed gear Engine speed >300 rpm Contaminated oil check if DTC sets
ratio in GEAR 1 or within the evaluation
Engine not in LHM Mechanical damage conditions
GEAR MANUAL 1 is
incorrect Transmission oil temperature TCU Check oil level
>0C
Check oil quality
Transmission output shaft
speed >300 rpm Check for
mechanical damage
Transmission gear select
lever NOT in Neutral or Park Replace
transmission
P0732 Ignition key in ON position Low oil level Clear DTC and
The observed gear Engine speed >300 rpm Contaminated oil check if DTC sets
ratio in GEAR 2 is within the evaluation
Engine not in LHM Mechanical damage conditions
incorrect
Transmission oil temperature TCU Check oil level
>0C
Check oil quality
Transmission output shaft
speed >300 rpm Check for
mechanical damage
Transmission gear select
lever NOT in Neutral or Park Replace
transmission

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M78 Automatic Transmission Page49

DTC Evaluation Conditions Possible Causes Actions

P0733 Ignition key in ON position Low oil level Clear DTC and
The observed gear Engine speed >300 rpm Contaminated oil check if DTC sets
ratio in GEAR 3 is within the evaluation
Engine not in LHM Mechanical damage conditions
incorrect
Transmission oil temperature TCU Check oil level
>0C
Check oil quality
Transmission output shaft
speed >300 rpm Check for
mechanical damage
Transmission gear select
lever NOT in Neutral or Park Replace
transmission
P0734 Ignition key in ON position Low oil level Clear DTC and
The observed gear Engine speed >300 rpm Contaminated oil check if DTC sets
ratio in GEAR 4 is within the evaluation
Engine not in LHM Mechanical damage conditions
incorrect
Transmission oil temperature TCU Check oil level
>0C
Check oil quality
Transmission output shaft
speed >300 rpm Check for
mechanical damage
Transmission gear select
lever NOT in Neutral or Park Replace
transmission
P0735 Ignition key in ON position Low oil level Clear DTC and
The observed gear Engine speed >300 rpm Contaminated oil check if DTC sets
ratio in GEAR 5 is within the evaluation
Engine not in LHM Mechanical damage conditions
incorrect
Transmission oil temperature TCU Check oil level
>0C
Check oil quality
Transmission output shaft
speed >300 rpm Check for
mechanical damage
Transmission gear select
lever NOT in Neutral or Park Replace
transmission
P0736 Ignition key in ON position Low oil level Clear DTC and
The observed gear Engine speed >300 rpm Contaminated oil check if DTC sets
ratio in REVERSE is within the evaluation
Engine not in LHM Mechanical damage conditions
incorrect
Transmission oil temperature TCU Check oil level
>0C
Check oil quality
Transmission output shaft
speed >300 rpm Check for
mechanical damage
Transmission gear select
lever NOT in Neutral or Park Replace
transmission

DTC Clearing
DTC Conditions
P0729, P0731, Ignition ON
P0732, P0733,
Engine stopped
P0734, P0735 &
P0736 Scan tool

Torque Converter Control

The torque converter lock-up clutch is engaged and released via the hydraulic control system.
Pressure at the torque converter lock-up clutch piston is determined by an electronic variable bleed solenoid
(VBS). During operation, the TCU evaluates torque converter slip speed and compares this against what is expected. If
torque converter slip is not within predefined parameters, a DTC will set to indicate a torque converter lock-up problem.

DTC Title System Action

TCU SENDS MIL REQUEST ON
P0741 Torque converter clutch circuit stuck UNLOCKED
Torque converter remains in open state
TCU SENDS MIL REQUEST ON
P0742 Torque converter clutch circuit stuck LOCKED Torque converter remains in open state
with Solenoid S3 disabled
TCU SENDS MIL REQUEST ON
P0744 Torque converter clutch Slip Error
Torque converter remains in open state

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M78 Automatic Transmission Page50

Description
DTC Description
Torque converter stuck open when requested to lock. Slip speed is greater than 50 rpm for more than 0.5
P0741
seconds while locked state requested.
Torque converter stuck locked when requested to open. Slip speed is less than 150 rpm and engine torque
P0742
is greater than 150 Nm for more than 0.5 seconds while open state requested.

P0744 Torque converter slip speed cannot be controlled for more than 0.5 seconds.

DTC Details
DTC Evaluation Conditions Possible Causes Actions
P0741 Ignition key in ON position Low oil level Clear DTC and
Torque converter Engine speed >300 rpm Contaminated oil check if DTC sets
clutch circuit stuck within the evaluation
Engine not in LHM Mechanical damage conditions
OFF
Transmission oil temperature TCU Check oil level
>0C
Check oil quality
Transmission NOT shifting
Check for
Transmission gear select mechanical damage
lever in Drive
Replace
transmission
P0742 Ignition key in ON position Low oil level Clear DTC and
Torque converter Engine speed >300 rpm Contaminated oil check if DTC sets
clutch circuit stuck within the evaluation
Engine not in LHM Mechanical damage conditions
ON
Transmission oil temperature TCU Check oil level
>0C
Check oil quality
Transmission NOT shifting
Check for
Transmission gear select mechanical damage
lever in Drive
Replace
transmission
P0744 Ignition key in ON position Low oil level Clear DTC and
Torque converter Engine speed >300 rpm Contaminated oil check if DTC sets
clutch Slip Error within the evaluation
Engine not in LHM Mechanical damage conditions
Transmission oil temperature TCU Check oil level
>0C
Check oil quality
Transmission NOT shifting
Check for
Transmission gear select mechanical damage
lever in Drive
Replace
transmission

DTC Clearing
DTC Conditions
P0741, P0742 & Ignition ON
P0744
Engine stopped
Scan tool

Steering Wheel
The steering wheel contains transmission gear select (TGS) up/down switches and are directly connected to the TCU.
These switches operate in parallel with the TGS lever switches directly to the TCU.

DTC Title System Action

Manual Shift Control Up/Down (Steering Wheel) Switch Manual shift control (steering wheel)
P0826
Stuck switches disabled
Manual Shift Control Up/Down (Steering Wheel) Switch Manual shift control (steering wheel)
P0827
Signal Low switches disabled
Manual Shift Control Up/Down (Steering Wheel) Switch Manual shift control (steering wheel)
P0828
Signal High switches disabled

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M78 Automatic Transmission Page51

Description
DTC Description
The Manual Shift Control Up/Down (Steering Wheel) switch has been depressed for more than 120
P0826
seconds continuously. This may indicate a faulty switch
The Manual Shift Control Up/Down (Steering Wheel) switch signal is giving a value indicative of a short
P0827
circuit
The Manual Shift Control Up/Down (Steering Wheel) switch signal is giving a value indicative of an open
P0828
circuit

Schematic

Connector Details

Resistance Values

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M78 Automatic Transmission Page52

DTC Details
DTC Evaluation Conditions Possible Causes Actions
P0826 Ignition key in ON position Shift Control Clear DTC and
Manual Shift Control Up/Down Switch check if DTC sets
Up/Down (Steering (steering wheel) within the evaluation
Wheel) Switch Stuck TCU to Shift Control conditions
Up/Down switch Check up/down
harness and/or switch (steering
connector fault wheel) mechanical
TCU operation
Check circuit
between terminal J2-
9 and Shift Control
Up/Down switch
(steering wheel) for
short or open
condition
Check circuit
between terminals
J3-15 and steering
wheel for short or
open condition
Disconnect TCU
connectors J2 & J3
and measure
resistance across
terminals J2-9 and
J3-15. Refer to the
resistance table
above for
specifications.
Replace range
up/down switch
(steering wheel) if
the resistance values
are outside of the
specified range
Replace TCU
P0827 Ignition key in ON position Shift Control Clear DTC and
Manual Shift Control Up/Down Switch check if DTC sets
Up/Down (Steering (steering wheel) within the evaluation
Wheel) Switch Signal TCU to Shift Control conditions
Low Up/Down switch Check up/down
harness and/or switch (steering
connector fault wheel) mechanical
TCU operation
Check circuit
between terminal J2-
9 and Shift Control
Up/Down switch
(steering wheel) for
short or open
condition
Check circuit
between terminals
J3-15 and steering
wheel for short or
open condition
Disconnect TCU
connectors J2 & J3
and measure
resistance across
terminals J2-9 and
J3-15. Refer to the
resistance table
above for
specifications.
Replace range
up/down switch
(steering wheel) if
the resistance values
are outside of the
specified range
Replace TCU

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M78 Automatic Transmission Page53

DTC Evaluation Conditions Possible Causes Actions

P0828 Ignition key in ON position Shift Control Clear DTC and
Manual Shift Control Up/Down Switch check if DTC sets
Up/Down (Steering (steering wheel) within the evaluation
Wheel) Switch Signal TCU to Shift Control conditions
High Up/Down switch Check up/down
harness and/or switch (TGS)
connector fault mechanical operation
TCU Check circuit
between terminal J2-
4 and Shift Control
Up/Down switch
(TGS) for short or
open condition
Check circuit
between terminals
J3-15 and TGS
Lever for short or
open condition
Disconnect TCU
connectors J2 & J3
and measure
resistance across
terminals J2-9 and
J3-15. Refer to the
resistance table
above for
specifications.
Replace range
up/down switch
(steering wheel) if
the resistance values
are outside of the
specified range
Replace TCU

DTC Clearing
DTC Conditions
P0826, P0827 & Ignition ON
P0828
Engine stopped
Scan tool

Variable Bleed Solenoids

The transmission control unit uses variable bleed solenoids to regulate hydraulic pressure. This hydraulic pressure
controls torque flow through clutch elements within the transmission.
The TCU is able to vary the amount of torque applied to the clutch elements by controlling the current to the variable
bleed solenoid windings. The clutch element torque transfer is directly related to the current applied to the solenoids.
During operation, the TCU evaluates the actual current delivered to the solenoid and compares this against what is
expected. If the current is not within predefined parameters, a DTC will be set to indicate the load on the TCU is
abnormal.

DTC Title System Action

TCU SENDS MIL REQUEST ON
P0962 Solenoid S9 Over Current
Transmission in LHM
TCU SENDS MIL REQUEST ON
P0963 Solenoid S9 Low Current
Transmission in LHM
TCU SENDS MIL REQUEST ON
P0966 Solenoid S10 Over Current
Transmission in LHM
TCU SENDS MIL REQUEST ON
P0967 Solenoid S10 Low Current
Transmission in LHM
TCU SENDS MIL REQUEST ON
P0985 Solenoid S5 Over Current
Transmission in LHM
TCU SENDS MIL REQUEST ON
P0986 Solenoid S5 Low Current
Transmission in LHM

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M78 Automatic Transmission Page54

DTC Title System Action

TCU SENDS MIL REQUEST ON
P0998 Solenoid S6 Over Current
Transmission in LHM
TCU SENDS MIL REQUEST ON
P0999 Solenoid S6 Low Current
Transmission in LHM
TCU SENDS MIL REQUEST ON
P099B Solenoid S7 Over Current
Transmission in LHM
TCU SENDS MIL REQUEST ON
P099C Solenoid S7 Low Current
Transmission in LHM
TCU SENDS MIL REQUEST ON
P099E Solenoid S8 Over Current
Transmission in LHM
TCU SENDS MIL REQUEST ON
P099F Solenoid S8 Low Current
Transmission in LHM

Description
DTC Description
P0962 The Variable Bleed Solenoid S9 feedback indicates a short circuit.

P0963 The Variable Bleed Solenoid S9 feedback indicates an open circuit

P0966 The Variable Bleed Solenoid S10 feedback indicates a short circuit

P0967 The Variable Bleed Solenoid S10 feedback indicates an open circuit

P0985 The Variable Bleed Solenoid S5 feedback indicates a short circuit

P0986 The Variable Bleed Solenoid S5 feedback indicates an open circuit

P0998 The Variable Bleed Solenoid S6 feedback indicates a short circuit

P0999 The Variable Bleed Solenoid S6 feedback indicates an open circuit

P099B The Variable Bleed Solenoid S7 feedback indicates a short circuit

P099C The Variable Bleed Solenoid S7 feedback indicates an open circuit

P099E The Variable Bleed Solenoid S8 feedback indicates a short circuit

P099F The Variable Bleed Solenoid S8 feedback indicates an open circuit

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M78 Automatic Transmission Page55

Schematic

Connector Details

DTC Details
DTC Evaluation Conditions Possible Causes Actions
P0962 Ignition key in ON position TCU to Clear DTC and
Solenoid S9 Over Solenoid energised Transmission check if DTC sets
Current harness and/or within the evaluation
TCU supply voltage OK connector fault conditions
Transmission Check circuit
internal harness between terminals
and/or connector J4-6 and J1-1 for
fault short or open
VBS9 condition

TCU Check circuit

between terminals
J4-1 and J1-7 for
short or open
condition
Check between
terminals J4-1 and
J4-6 for solenoid
resistance of 4.14
0.3 . Replace
transmission if value
is outside of this
range.
Replace TCU

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M78 Automatic Transmission Page56

DTC Evaluation Conditions Possible Causes Actions

P0963 Ignition key in ON position TCU to Clear DTC and
Solenoid S9 Low Solenoid energised Transmission check if DTC sets
Current harness and/or within the evaluation
TCU supply voltage OK connector fault conditions
Transmission Check circuit
internal harness between terminals
and/or connector J4-6 and J1-1 for
fault short or open
VBS9 condition

TCU Check circuit

between terminals
J4-1 and J1-7 for
short or open
condition
Check between
terminals J4-1 and
J4-6 for solenoid
resistance of 4.14
0.3 . Replace
transmission if value
is outside of this
range.
Replace TCU
P0966 Ignition key in ON position TCU to Clear DTC and
Solenoid S10 Over Solenoid energised Transmission check if DTC sets
Current harness and/or within the evaluation
TCU supply voltage OK connector fault conditions
Transmission Check circuit
internal harness between terminals
and/or connector J4-7 and J1-2 for
fault short or open
VBS10 condition

TCU Check circuit

between terminals
J4-1 and J1-7 for
short or open
condition
Check between
terminals J4-1 and
J4-7 for solenoid
resistance of 4.14
0.3 . Replace
transmission if value
is outside of this
range.
Replace TCU
P0967 Ignition key in ON position TCU to Clear DTC and
Solenoid S10 Low Solenoid energised Transmission check if DTC sets
Current harness and/or within the evaluation
TCU supply voltage OK connector fault conditions
Transmission Check circuit
internal harness between terminals
and/or connector J4-7 and J1-2 for
fault short or open
VBS10 condition

TCU Check circuit

between terminals
J4-1 and J1-7 for
short or open
condition
Check between
terminals J4-1 and
J4-7 for solenoid
resistance of 4.14
0.3 . Replace
transmission if value
is outside of this
range.
Replace TCU

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M78 Automatic Transmission Page57

DTC Evaluation Conditions Possible Causes Actions

P0985 Ignition key in ON position TCU to Clear DTC and
Solenoid S5 Over Solenoid energised Transmission check if DTC sets
Current harness and/or within the evaluation
TCU supply voltage OK connector fault conditions
Transmission Check circuit
internal harness between terminals
and/or connector J4-2 and J1-5 for
fault short or open
VBS5 condition

TCU Check circuit

between terminals
J4-1 and J1-7 for
short or open
condition
Check between
terminals J4-1 and
J4-2 for solenoid
resistance of 4.14
0.3 . Replace
transmission if value
is outside of this
range.
Replace TCU
P0986 Ignition key in ON position TCU to Clear DTC and
Solenoid S5 Low Solenoid energised Transmission check if DTC sets
Current harness and/or within the evaluation
TCU supply voltage OK connector fault conditions
Transmission Check circuit
internal harness between terminals
and/or connector J4-2 and J1-5 for
fault short or open
VBS5 condition

TCU Check circuit

between terminals
J4-1 and J1-7 for
short or open
condition
Check between
terminals J4-1 and
J4-2 for solenoid
resistance of 4.14
0.3 . Replace
transmission if value
is outside of this
range.
Replace TCU
P0998 Ignition key in ON position TCU to Clear DTC and
Solenoid S6 Over Solenoid energised Transmission check if DTC sets
Current harness and/or within the evaluation
TCU supply voltage OK connector fault conditions
Transmission Check circuit
internal harness between terminals
and/or connector J4-3 and J1-6 for
fault short or open
VBS6 condition

TCU Check circuit

between terminals
J4-1 and J1-7 for
short or open
condition
Check between
terminals J4-1 and
J4-3 for solenoid
resistance of 4.14
0.3 . Replace
transmission if value
is outside of this
range.
Replace TCU

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M78 Automatic Transmission Page58

DTC Evaluation Conditions Possible Causes Actions

P0999 Ignition key in ON position TCU to Clear DTC and
Solenoid S6 Low Solenoid energised Transmission check if DTC sets
Current harness and/or within the evaluation
TCU supply voltage OK connector fault conditions
Transmission Check circuit
internal harness between terminals
and/or connector J4-3 and J1-6 for
fault short or open
VBS6 condition

TCU Check circuit

between terminals
J4-1 and J1-7 for
short or open
condition
Check between
terminals J4-1 and
J4-3 for solenoid
resistance of 4.14
0.3 . Replace
transmission if value
is outside of this
range.
Replace TCU
P099B Ignition key in ON position TCU to Clear DTC and
Solenoid S7 Over Solenoid energised Transmission check if DTC sets
Current harness and/or within the evaluation
TCU supply voltage OK connector fault conditions
Transmission Check circuit
internal harness between terminals
and/or connector J4-4 and J1-3 for
fault short or open
VBS7 condition

TCU Check circuit

between terminals
J4-1 and J1-7 for
short or open
condition
Check between
terminals J4-1 and
J4-4 for solenoid
resistance of 4.14
0.3 . Replace
transmission if value
is outside of this
range.
Replace TCU
P099C Ignition key in ON position TCU to Clear DTC and
Solenoid S7 Low Solenoid energised Transmission check if DTC sets
Current harness and/or within the evaluation
TCU supply voltage OK connector fault conditions
Transmission Check circuit
internal harness between terminals
and/or connector J4-4 and J1-3 for
fault short or open
VBS7 condition

TCU Check circuit

between terminals
J4-1 and J1-7 for
short or open
condition
Check between
terminals J4-1 and
J4-4 for solenoid
resistance of 4.14
0.3 . Replace
transmission if value
is outside of this
range.
Replace TCU

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M78 Automatic Transmission Page59

DTC Evaluation Conditions Possible Causes Actions

P099E Ignition key in ON position TCU to Clear DTC and
Solenoid S8 Over Solenoid energised Transmission check if DTC sets
Current harness and/or within the evaluation
TCU supply voltage OK connector fault conditions
Transmission Check circuit
internal harness between terminals
and/or connector J4-5 and J1-4 for
fault short or open
VBS8 condition

TCU Check circuit

between terminals
J4-1 and J1-7 for
short or open
condition
Check between
terminals J4-1 and
J4-5 for solenoid
resistance of 4.14
0.3 . Replace
transmission if value
is outside of this
range.
Replace TCU
P099F Ignition key in ON position TCU to Clear DTC and
Solenoid S8 Low Solenoid energised Transmission check if DTC sets
Current harness and/or within the evaluation
TCU supply voltage OK connector fault conditions
Transmission Check circuit
internal harness between terminals
and/or connector J4-5 and J1-4 for
fault short or open
VBS8 condition

TCU Check circuit

between terminals
J4-1 and J1-7 for
short or open
condition
Check between
terminals J4-1 and
J4-5 for solenoid
resistance of 4.14
0.3 . Replace
transmission if value
is outside of this
range.
Replace TCU

DTC Clearing
DTC Conditions
P0962, P0963, Ignition ON
P0966, P0967,
Engine stopped
P0985, P0986,
P0998, P0999, Scan tool
P099B, P099C,
P099E & P099F

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M78 Automatic Transmission Page60

On/Off Solenoids
The TCU uses on/off solenoids to select between different clutch elements within the transmission.
During operation, the TCU evaluates the actual current delivered to the on/off solenoid and compares this against what is
expected. If the current is not within predefined parameters, a DTC will be set to indicate the load on the TCU is
abnormal.

DTC Title System Action

TCU SENDS MIL REQUEST ON
P0973 Solenoid S1 Over Current
Transmission in LHM
TCU SENDS MIL REQUEST ON
P0974 Solenoid S1 Low Current
Transmission in LHM
TCU SENDS MIL REQUEST ON
P0976 Solenoid S2 Over Current
Transmission in LHM
TCU SENDS MIL REQUEST ON
P0977 Solenoid S2 Low Current
Transmission in LHM
TCU SENDS MIL REQUEST ON
P0979 Solenoid S3 Over Current
Transmission in LHM
TCU SENDS MIL REQUEST ON
P0980 Solenoid S3 Low Current
Transmission in LHM
TCU SENDS MIL REQUEST ON
P0982 Solenoid S4 Over Current
Transmission in LHM
TCU SENDS MIL REQUEST ON
P0983 Solenoid S4 Low Current
Transmission in LHM

Description
DTC Description
P0973 The On/Off Solenoid S1 feedback indicates a short circuit

P0974 The On/Off Solenoid S1 feedback indicates an open circuit

P0976 The On/Off Solenoid S2 feedback indicates a short circuit

P0977 The On/Off Solenoid S2 feedback indicates an open circuit

P0979 The On/Off Solenoid S3 feedback indicates a short circuit

P0980 The On/Off Solenoid S3 feedback indicates an open circuit

P0982 The On/Off Solenoid S4 feedback indicates a short circuit

P0983 The On/Off Solenoid S4 feedback indicates an open circuit

Schematic

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M78 Automatic Transmission Page61

Connector Details

DTC Details
DTC Evaluation Conditions Possible Causes Actions
P0973 Ignition key in ON position TCU to Clear DTC and
Solenoid S1 Over Solenoid energised Transmission check if DTC sets
Current harness and/or within the evaluation
TCU supply voltage OK connector fault conditions
Transmission Check circuit
internal harness between terminals
and/or connector J4-21 and J1-10 for
fault short or open
On/Off Solenoid 1 condition

TCU Check circuit

between terminals
J4-20 and J1-15 for
short or open
condition
Check between
terminals J4-20 and
J4-21 for solenoid
resistance of 22.0
1.2 . Replace
transmission if value
is outside of this
range.
Replace TCU
P0974 Ignition key in ON position TCU to Clear DTC and
Solenoid S1 Low Solenoid energised Transmission check if DTC sets
Current harness and/or within the evaluation
TCU supply voltage OK connector fault conditions
Transmission Check circuit
internal harness between terminals
and/or connector J4-21 and J1-10 for
fault short or open
On/Off Solenoid 1 condition

TCU Check circuit

between terminals
J4-20 and J1-15 for
short or open
condition
Check between
terminals J4-20 and
J4-21 for solenoid
resistance of 22.0
1.2 . Replace
transmission if value
is outside of this
range.
Replace TCU

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M78 Automatic Transmission Page62

DTC Evaluation Conditions Possible Causes Actions

P0976 Ignition key in ON position TCU to Clear DTC and
Solenoid S2 Over Solenoid energised Transmission check if DTC sets
Current harness and/or within the evaluation
TCU supply voltage OK connector fault conditions
Transmission Check circuit
internal harness between terminals
and/or connector J4-22 and J1-9 for
fault short or open
On/Off Solenoid 2 condition

TCU Check circuit

between terminals
J4-20 and J1-15 for
short or open
condition
Check between
terminals J4-20 and
J4-22 for solenoid
resistance of 22.0
1.2 . Replace
transmission if value
is outside of this
range.
Replace TCU
P0977 Ignition key in ON position TCU to Clear DTC and
Solenoid S2 Low Solenoid energised Transmission check if DTC sets
Current harness and/or within the evaluation
TCU supply voltage OK connector fault conditions
Transmission Check circuit
internal harness between terminals
and/or connector J4-22 and J1-9 for
fault short or open
On/Off Solenoid 2 condition

TCU Check circuit

between terminals
J4-20 and J1-15 for
short or open
condition
Check between
terminals J4-20 and
J4-22 for solenoid
resistance of 22.0
1.2 . Replace
transmission if value
is outside of this
range.
Replace TCU
P0979 Ignition key in ON position TCU to Clear DTC and
Solenoid S3 Over Solenoid energised Transmission check if DTC sets
Current harness and/or within the evaluation
TCU supply voltage OK connector fault conditions
Transmission Check circuit
internal harness between terminals
and/or connector J4-23 and J1-12 for
fault short or open
On/Off Solenoid 3 condition

TCU Check circuit

between terminals
J4-20 and J1-15 for
short or open
condition
Check between
terminals J4-20 and
J4-23 for solenoid
resistance of 22.0
1.2 . Replace
transmission if value
is outside of this
range.
Replace TCU

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M78 Automatic Transmission Page63

DTC Evaluation Conditions Possible Causes Actions

P0980 Ignition key in ON position TCU to Clear DTC and
Solenoid S3 Low Solenoid energised Transmission check if DTC sets
Current harness and/or within the evaluation
TCU supply voltage OK connector fault conditions
Transmission Check circuit
internal harness between terminals
and/or connector J4-23 and J1-12 for
fault short or open
On/Off Solenoid 3 condition

TCU Check circuit

between terminals
J4-20 and J1-15 for
short or open
condition
Check between
terminals J4-20 and
J4-23 for solenoid
resistance of 22.0
1.2 . Replace
transmission if value
is outside of this
range.
Replace TCU
P0982 Ignition key in ON position TCU to Clear DTC and
Solenoid S4 Over Solenoid energised Transmission check if DTC sets
Current harness and/or within the evaluation
TCU supply voltage OK connector fault conditions
Transmission Check circuit
internal harness between terminals
and/or connector J4-24 and J1-11 for
fault short or open
On/Off Solenoid 4 condition

TCU Check circuit

between terminals
J4-20 and J1-15 for
short or open
condition
Check between
terminals J4-20 and
J4-24 for solenoid
resistance of 22.0
1.2 . Replace
transmission if value
is outside of this
range.
Replace TCU
P0983 Ignition key in ON position TCU to Clear DTC and
Solenoid S4 Low Solenoid energised Transmission check if DTC sets
Current harness and/or within the evaluation
TCU supply voltage OK connector fault conditions
Transmission Check circuit
internal harness between terminals
and/or connector J4-24 and J1-11 for
fault short or open
On/Off Solenoid 4 condition

TCU Check circuit

between terminals
J4-20 and J1-15 for
short or open
condition
Check between
terminals J4-20 and
J4-24 for solenoid
resistance of 22.0
1.2 . Replace
transmission if value
is outside of this
range.
Replace TCU

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M78 Automatic Transmission Page64

DTC Clearing
DTC Conditions
P0973, P0974, Ignition ON
P0976, P0977,
Engine stopped
P0979, P0980,
P0982 & P0983 Scan tool

CAN Network
The Controller Area Network (CAN) bus is used to share vehicle system information between the control
units connected to the bus. The TCU obtains the majority if its information via this network. If the TCU does
not receive information at regular intervals from the electronic control units connected to the bus, the TCU
will set a communication DTC.

DTC Title System Action

Cyclic CAN messages from Engine ECU are None
U0100
unavailable
Cyclic CAN messages from Transfer Case Control None
U0102
Unit are unavailable
Cyclic CAN messages from Brake System Control None
U0121
Unit (ABS/ESP/TCS) are unavailable
CAN signals from Engine ECU are out of range or None
U0401
Invalid
CAN signals from Transfer Case Control Unit are 2WD assumed by TCU
U0403
out of range or Invalid
CAN signals from Brake System Control Unit None
U0415
(ABS/ESP/TCS) are out of range or Invalid

DTC Description
DTC Description
U0100 CAN Message not available

U0102 CAN Message not available

U0121 CAN Message not available

U0401 CAN Message not available

U0403 CAN Message not available

U0415 CAN Message not available

Schematic

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M78 Automatic Transmission Page65

Connector Details

DTC Details
DTC Evaluation Conditions Possible Causes Actions
U0100 Ignition key in ON position Wiring harness Clear DTC and
Cyclic CAN messages for longer than 1 second and/or connector check if DTC sets
from Engine ECU are CAN Message from Engine fault within the evaluation
unavailable ECU not received for five Engine ECU system conditions
U0401 message cycles fault Check Engine ECU
TCU system
CAN signals from
Engine ECU are out of Check circuit
range or Invalid between terminal
J2-1 and Engine
ECU for short or
open condition.
Refer to vehicle
CAN communication
diagnostics for
further information
Check circuit
between terminal
J2-7 and Engine
ECU for short or
open condition.
Refer to vehicle
CAN communication
diagnostics for
further information
Replace TCU
U0102 Ignition key in ON position Wiring harness Clear DTC and
Cyclic CAN messages for longer than 1 second and/or connector check if DTC sets
from Transfer Case CAN Message from Transfer fault within the evaluation
Control Unit are Case Control Unit not Transfer Case conditions
unavailable received for five message system fault Check Transfer
U0403 cycles TCU Case Control Unit
CAN signals from Check circuit
Transfer Case Control between terminal
Unit are out of range J2-1 and Transfer
or Invalid Case Control Unit
for short or open
condition. Refer to
vehicle CAN
communication
diagnostics for
further information
Check circuit
between terminal
J2-7 and Transfer
Case Control Unit
for short or open
condition. Refer to
vehicle CAN
communication
diagnostics for
further information
Replace TCU
U0121 Ignition key in ON position Wiring harness Clear DTC and
Cyclic CAN messages for longer than 1 second and/or connector check if DTC sets
within the evaluation

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M78 Automatic Transmission Page66

DTC Evaluation Conditions Possible Causes Actions

from Brake System CAN Message from Brake fault conditions
Control Unit System Control Unit not Brake system fault Check Brake
(ABS/ESP/TCS) are received for five message System Control Unit
unavailable TCU
cycles DTCs
U0415
Check circuit
CAN signals from between terminal
Brake System Control J2-1 and Brake
Unit (ABS/ESP/TCS) System Control Unit
are out of range or for short or open
Invalid condition. Refer to
vehicle CAN
communication
diagnostics for
further information
Check circuit
between terminal
J2-7 and Brake
System Control Unit
for short or open
condition. Refer to
vehicle CAN
communication
diagnostics for
further information
Replace TCU

DTC Clearing
DTC Conditions
U0100, U0102, Ignition ON
U0121, U0401,
Engine stopped
U0403,
& U0415 Scan tool

TCU Calibration
TCU software or calibration may be upgraded at service. These DTCs protect the TCU against corrupted
files being loaded into the TCU. They also ensure only the correct calibration parameters are used with the
software version currently loaded into the TCU.

DTC Title System Action

U1601 TCU Application Software Missing or Corrupted Transmission in LHM

U1606 TCU Calibration Error Platform TCU SENDS MIL REQUEST ON

U1607 TCU Calibration Error - Active Variant TCU SENDS MIL REQUEST ON

U1608 TCU VIN Coding Error TCU SENDS MIL REQUEST ON

U1609 TCU Hardware (pcb) Calibration Error TCU SENDS MIL REQUEST ON

DTC Description
DTC Description
During initialisation, the TCU software was found to be missing or corrupted. In this condition the TCU will
U1601
not operate, and the transmission will be in LHM

U1606 Platform calibration data CRC check failed at initialisation of TCU. This is normal for a development TCU

Active Variant calibration data CRC check failed at initialisation of TCU.

U1607
This is normal for a development TCU

U1608 VIN based variant could not be determined. TCU will use default VIN calibration

U1609 Calibration for TCU hardware (pcb) is missing or corrupted. TCU will use default calibration

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M78 Automatic Transmission Page67

DTC Details
DTC Evaluation Conditions Possible Causes Actions
U1601 Ignition key in ON position Corrupt application Clear DTC and
TCU Application CRC not Valid check if DTC sets
Software Missing or within the evaluation
Corrupted conditions
Update TCU
calibration software.
Refer to vehicle
scan tool
documentation for
further information
Replace TCU
U1606 Ignition key in ON position TCU calibration Clear DTC and
TCU Calibration Error CRC not valid check if DTC sets
Platform within the evaluation
conditions
U1607
Update TCU
TCU Calibration Error
calibration software.
- Active Variant
Refer to vehicle
scan tool
documentation for
further information
Replace TCU
U1608 Ignition key in ON position TCU calibration Clear DTC and
TCU VIN Coding Error VIN not compatible with TCU replaced but check if DTC sets
calibration VIN code not set. within the evaluation
conditions
Update TCU
calibration software.
Refer to vehicle
scan tool
documentation for
further information
U1609 Ignition key in ON position TCU Clear DTC and
TCU Hardware (pcb) TCU manufacturing check if DTC sets
Calibration Error information not present within the evaluation
conditions
Replace TCU

DTC Clearing
DTC Conditions
U1601, U1606, Ignition ON
U1607,
Engine stopped
U1608 & U1609
Scan tool

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M78 Automatic Transmission Page68

3 Maintenance Operations
3.1 Stall Test
Stall testing can be performed on the Model 78 6 speed automatic transmission to determine whether the
transmission clutches can hold the full engine torque without slipping.
Stall testing should be performed for a period no longer then 10 seconds.
Apply Hand Brake
Start Engine
Press Brake Pedal
Shift to DRIVE
Press Accelerator Pedal to 100 % for 6 seconds
Observe Engine speed
Release Accelerator Pedal
Shift To Reverse
Press Accelerator Pedal to 100 % for 6 seconds
Observe Engine speed
If engine speed is observed > 3000 rpm; transmission hardware failure

3.2 Transmission Reset Procedure (Replacement Transmission)

It is necessary to reset the adaptive data stored within the transmission control unit (TCU) when the
transmission and or TCU have been replaced.

Green Offset Reset

Carried out when a replacement transmission has been installed in a vehicle.

Adaptive Reset
Carried out when one of the following has occurred:
Replace transmission
Replace TCU

Green Offset Reset Procedure

To perform a green offset reset procedure, proceed as follows:
1. Connect the vehicles diagnostic scan tool to the vehicles diagnostic connector. Refer to the vehicle
repair manual for information on connecting the scan tool.
2. With the transmission gear select (TGS) lever in Park, turn the ignition key to the ON position
(engine not running).
3. Using the scan tool, set the parameter Set Km Travelled to 0Km.
4. Run the task Activate Adaptive Green Offset.
5. Turn the ignition key to the OFF position.
6. Start the vehicle and check for normal operation.

Adaptive Reset Procedure

To perform an adaptive reset procedure, proceed as follows:
1. Connect the vehicles diagnostic scan tool to the vehicles diagnostic connector. Refer to the vehicle
repair manual for information on connecting the scan tool.
2. With the transmission gear select (TGS) lever in Park, turn the ignition key to the ON position
(engine not running).
3. Set the parameter Set Km Travelled to 0 Km.
4. Run the task Reset Adaptive Data.
5. Turn the ignition key to the OFF position.
6. Start the vehicle and check for normal operation.

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M78 Automatic Transmission Page69

3.3 Fluid Level Inspection

NOTE
As the temperature of the transmission
fluid greatly affects the fluid level, this
procedure must only be carried out with
the transmission fluid temperature below
50 C). If the transmission fluid
temperature is greater than 50C and the
correct procedure is not followed, the
result could be a false reading of the fluid
level.
Fluid level inspection must be carried out
with the vehicle level.

Caltex PED 1712 ATF must be used.

1 Raise the vehicle on a certified hoist. Refer to the vehicle repair manual for the location of jacking and
support points.
2 Place a drain container below the fluid level hole
and remove the transmission fluid level plug (1).
3 If fluid starts to drain from the fluid level hole,
reinstall the fluid level plug. If no fluid drains from
the fluid level hole, fill the transmission until fluid
starts to drain from the level hole and reinstall
the plug.
4 Drive the vehicle for approximately five minutes.
5 Connect the vehicles diagnostic scan tool to the
vehicles diagnostic connector. Refer to the
vehicle repair manual for information on
connecting the scan tool.
6 With the gear select lever in the Neutral position,
start the engine and allow to run at idle until the
transmission fluid temperature reaches 50C.

NOTE
Use the scan tool to monitor the
transmission fluid temperature.

7 Raise the vehicle on a certified hoist.

8 When the transmission fluid temperature reaches
50C turn off the engine.
9 Place a drain container below the fluid level hole
and remove the transmission fluid level plug.
Allow transmission fluid to drain from the fluid
level hole for 50 seconds.
10 Reinstall the fluid level plug and tighten the plug
to the correct torque specification.
Transmission fluid level plug
torque specification.............................. 30 35 Nm
11 Lower the vehicle to the ground and road test the
vehicle to check vehicle operation and for fluid
leaks.

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M78 Automatic Transmission Page70

3.4 Transmission Cooler and Hydraulic Line Flushing Procedure (New

Transmission)

NOTE
To prevent transmission damage due to
contaminants being present in the
transmission cooler and/or hydraulic lines,
the cooler and lines must be flushed.

1 Raise the vehicle on a certified hoist. Refer to the vehicle repair manual for the location of jacking and
support points.
2 Using compressed air, clear the cooler lines of any residual fluid.
3 Connect the front transmission cooler line to the transmission.
Front transmission cooler line
to transmission fitting
torque specification.............................. 25 35 Nm
4 Connect one end of a rubber hose to the end of the rear cooler line and place the other end in a
suitable container to collect the transmission fluid as it is pumped out.
5 Start the engine and run for approximately 30 seconds at idle. (With ATF at 50C temperature, a
minimum of 2.5litres oil flow after 30 seconds.)
6 Whist the engine is running, have an assistant pump transmission fluid into the transmission fluid level
hole.
7 Connect the rear transmission cooler line to the transmission.
Rear transmission cooler line
to transmission fitting
torque specification.............................. 25 35 Nm
8 Check the transmission fluid level; refer to Fluid Level Inspection on page 69.

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M78 Automatic Transmission Page71

4 Lubrication
Automatic transmission fluid ................................................... Caltex PED 1712 ATF

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M78 Automatic Transmission Page72

5 Torque Specifications
Transmission fluid level plug .................................................................... 30 35 Nm
Front transmission cooler line to transmission connector........................ 25 35 Nm
Rear transmission cooler line to transmission cooler connector.............. 25 35 Nm
Torque converter to drive plate bolt ......................................................... 40 42 Nm
Transmission selector lever to cross shaft nut......................................... 14 20 Nm

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 Appendix I

CDPF
L/Differential

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 CDPF
(Catalyst & Diesel Particulate Filter)
OVERVIEW

TEMP. Distribution for D27DTP

Throttle Body

Combustion Camber
1000 ~ 1300

Intercooler

DPF
600
Temp. Sensor

Turbo Charger HFM Sensor

Diff.l Pressure Sensor

Turbo Charger
DOC Opening
300 ~ 500 780 ~ 810
COMPONENTS

Front Temp.
Sensor
Diff. Pressure
Sensor

Front Pressure
Port
Turbo
Rear Temp. Charger
Sensor

Rear Pressure
Port
CDPF
 OPERATING PRINCIPLE I

Soot Filtering Procedure Soot Burning Procedure

Diff. Pressure
Diff. Pressure Sensor
Soot Burring
Soot Filtering Sensor Stage
Stage
Exh Exha
ENGINE ust
ENGINE aust Increase Gas
Gas exhaust gas
temperature
Exhaust Temp.
Exhaust Temp. Sensor
Sensor Post
Pilot & Main Injection
Injection

Intake Air Volume Intake Air Volume

Booster Pressure Sensor Booster Pressure Sensor
Detect the soot mass
exceeds the limit
3 Front Temp. Sensor : Installed before DOC and monitor the exhaust gas temperature
and protect the turbo charger
3 Rear Temp. Sensor : Installed in DPF and monitor the exhaust gas temperature to
maintain 600
+ Higher than 600 : lower CDPF durability Post injection is not performed or decreased
+ Less than 600 : lower CDPF efficiency Post injection amount is increased
3 Diff. Pressure Sensor : Calculate accumulated soot mass by measuring pressure
difference between front and rear side of CDPF
3 Throttle Body : When the engine running at low load range, throttle flap is closed to
decrease intake air amount and to increase the combustion temperature
OPERATING PRINCIPLE II
OPERATING PRINCIPLE III

F
DP
C
DO

CDPF : Integrated Filter including DOC [Diesel Oxydation Catalyst] +

DPF [Diesel Particulate Filter]

+ CO + 1/2O2 CO2 DOC

+ HC + O2 H2O + CO2 CDPF
+ PM Burning H2O + CO2 DPF
+ NOX Inhibition EGR SYSTEM
 SENSOR SPECIFICATION

Temperature Sensor Diff. Pressure Sensor

; #1 & #2 (200)
Output

Pressure Diff. (mbar)

2.5 800
Voltage

2.0
600

1.5

400

1.0

200
0.5

0.0 0
-19 0 59 140 221 319 420 518 621 718 894 0 1 2 3 4

Temp. C Output Voltage (V)

Temp. Voltage Temp. Voltage Pressure Voltage Pressure Voltage

() (V) () (V) Diff. (mbar) (V) Diff. (mbar) (V)
-19 0.782 319 1.510 0 0.5 470 3.0
0 0.836 420 1.672
100 1.0 560 3.5
59 0.987 518 1.808
180 1.5 660 4.0
140 1.168 621 1.935
370 2.5 750 4.5
221 1.334 718 2.043
 MAINTENANCE I

Pattern of Soot Deposit

1. Abnormal CDPF Soot Deposit 2. Normal CDPF Soot Deposit

Precaution to ensure CDPF maximum service life

Do not use inappropriate fuel Keep engine maintenance interval
Frequently check engine oil level Do not make necessary engine idling
Do not shut off engine while CDPF regeneration is in process
Do not use additives in engine oil and fuel
Do not drive long distance with engine CHECK lamp ON
Be sure to stay away the flammable materials from the exhaust pipe and the CDPF to
avoid getting burned
Regeneration may not be performed due to several operating conditions, in this case
engine CHECK lamp flashes ; Should drive the vehicle at high speed more than 1 per week
 MAINTENANCE II

SCAN100
 CDPF ENGINE OIL I

Characteristic of Specified Engine Oil for CDPF

3 Minimize ASH generation characteristic
3 Optimize fuel consumption rate due to high efficient and low viscosity
3 Minimize CO2 level in exhaust gas
3 Increase engine oil characteristic ; Durability, Cold start ability

Clogged by ASH
[CDPF inside]

Soot
HC
CO DOC DPF
CONO

Accumulated Soot
DOC + DPF = CDPF (integrated)
 CDPF ENGINE OIL II

Points at issue with wrong engine oil

3 Lower the CDPF life time (about 30%) by accumulated ASH in CDPF filter
3 Increase fuel consumption rate by engine frictional resistance, exhaust
resistance and frequent CDPF regeneration

Engine Oil Specification

CDPF equipped vehicle CDPF non Equipped Vehicle
Contents Approved by Approved by
MB SHEET 229.31 MB SHEET 229.1 / 229.3

Sulfated ASH 0.76% 1.17%

Phosphorous 0.075% 0.13%

Sulfur 0.15% 0.41%

SAE Standard 5W40 10W40

 LD
(Locking Differential)
INTRODUCTION

1. Locking differential
: The Locking Differential (LD) maximizes strengths of the differential and LSD systems and improves
off-road capability of the current LSD.

LH wheel :
150rpm
RH wheel :
250rpm

: 100~150rpm
(Locking)

When the difference between the rear left and right wheels speeds is unusually high
(for example, 100 rpm or higher, on a snow-covered, rainy, or water-covered road), it synchronizes
the rear axles and offers the maximum driving power to both rear wheels so that the vehicle can safely
move out of the road. In addition, a slight level of the LSD function keeps improving driving force on a
rough-surfaced road.

*Because of different size of cam plate diameter, minimum operating rpm could be different
OPERATING MECHANISM

1. The counter weight attached to the cam plate and case is rotating at the same speed of both wheels.
2. When there is a 100 rpm or more difference between the two wheels speeds, the wing-shaped fly weight inside the
counter weight is hooked to the latching brackets due to centrifugal force. This stops the counter weight.
3. Then, the halted counter weight stops the cam plate.
4. As the cam plate stops, the cam gears ramp and the cam plates ramp act against each other and move toward
the case.
5. The reaction force is transferred to the side gear of the other side through the reaction block. This force presses
the clutch disc pack on the other side and synchronizes the side gear and case.
6. If the vehicle is moving 32 km/h or faster, the locking will not engage for safe driving.
7. Because of the different weight center of the latching bracket attached to the case, the locking will not engage when
the cases rotating power increases and the power widens the latching bracket, in spite of widening the fly weight.
COMPONENTS

CASE PINION SHAFT

LOCK SCREW
FLANGE END
CLUTCH PACK
THRUST PINION SHAFT
WASHER

FUSE DISC

CAM SIDE
PINION GEAR
GEAR
THRUST WASHER
BUSHING
PINION GEAR
GUIDE CLIP
REACTION
BLOCK
SNAP RING BELL END
CLUTCH PACK
WAVE SPRING

CAM PLATE SHIM

LOCKING MECHANISM
(COUNTERWEIGHT)

LATCHING BRACKET
SIDE
(LOCKOUT)
GEAR