Troubleshooting

Marine
Industrial

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TABLE OF CONTENTS

TABLE OF CONTENTS

00 - GENERAL
DTC Status.......................................................................................................................................................................4
DTC status interpretation........................................................................................................................................4
Validate repair using DTC status........................................................................................................................... 6

21 - ENGINE
Relative Compression Test............................................................................................................................................ 8

23 - FUEL SYSTEM
Injector Test....................................................................................................................................................................12

25 - INLET & EXHAUST SYSTEM

eEPG, check...................................................................................................................................................................16
Preheat Relay, check..................................................................................................................................................... 17
Wastegate Valve, check................................................................................................................................................18
SCR NOx Conversion Test...........................................................................................................................................19
SCR Heating Phase.............................................................................................................................................. 22
NOx High Low Level............................................................................................................................................. 24
NOx Conversion Efficiency.................................................................................................................................. 25
NOx Zero Level...................................................................................................................................................... 26
Routine Response................................................................................................................................................. 27
NOx Interpretation................................................................................................................................................ 28
Routine Response Flow Chart............................................................................................................................. 29
Crystal Inspection......................................................................................................................................................... 34
Silencer/SCR Inspection............................................................................................................................................. 37
Regeneration................................................................................................................................................................. 42

26 - COOLING SYSTEM
Fan Control Test............................................................................................................................................................ 45

30 - ELECTRICAL SYSTEM
Smart Relay Module, check........................................................................................................................................ 47
Alternator Voltage Reducer, check.............................................................................................................................48
CAN Bus, check............................................................................................................................................................ 50
EMS, check................................................................................................................................................................... 52
HCU, check (EVC2)..................................................................................................................................................... 57
PCU, check....................................................................................................................................................................60

44 - TRANSMISSION
Steering Function DPI, check..................................................................................................................................... 63
Drive Position Angel Sensor, check..................................................................................................................... 67
Steering Motor, check...........................................................................................................................................68
VODIA Log Parameters, DPI............................................................................................................................... 69

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 00 - GENERAL

00 - GENERAL

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00 - GENERAL

DTC Status
Description
After a repair of a fault that triggered a DTC it is important to verify that the repair fixed the fault. The best way to do it
is by checking the DTC status. The status information of a DTC does not only show if a fault is active or not.
More important, the status also shows if the diagnostic monitor has run.

Diagnostic Monitor
There are different conditions that must be fulfilled before the diagnostic monitor for a DTC is run. Such conditions
can be: ignition on, engine running, engine speed higher than x, coolant temperature above y, etc.
A DTCs monitor conditions is described in the DTC workshop manual at the specific DTC at the “DTC Monitor Test
Condition” row.
The ECU checks the status of a DTC when all test conditions are met.

Active The diagnostic monitor has run and failed. There is an active fault detected.
The diagnostic monitor has run. No active fault found. Previously fault is no longer active. The
Inactive DTC stays “Inactive” until cleared or changes status to “Inactive Healed” after 40 cycles*.
Not all DTCs can be “Healed”.
Verified OK The diagnostic monitor has run. No fault found.
Undefined The diagnostic monitor has not run, conditions not fulfilled. DTC status unknown.
Inactive Healed A previously active DTC has been inactive for 40 cycles* and considered “Healed”.
*A cycle (drive cycle) is defined by OBD regulations where the OBD warm-up cycle is used in most cases when it
comes to a combustion engine. A warm-up cycle is defined by that the engine coolant temperature must rise more
than 22 degrees from engine start and reach at least 70 degrees.

DTC status interpretation

In this DTC read out example there are different statuses concerning booth the engine coolant temperature and the
engine coolant temperature sensor.

Engine Coolant Temperature Moderately High - P11E00= Verified OK

The diagnostic monitoring test has run without detecting any fault. It means that there is no issue detected with high
engine coolant temperature, hence “Verified OK”.

Engine Coolant Temperature Sensor 1 - P011513 = Inactive

The diagnostic monitoring test has run without detecting any active fault. Previously active fault is no longer active. In
this case it means that a previously detected circuit open has been evaluated OK during the last monitoring test.

Engine Coolant Temperature Sensor 1 - P01152A = Undefined

The diagnostic monitoring test has not run and therefore the status of this DTC is unknown/undefined. Undefined
does not mean that there is any fault just that the DTC monitoring test could not be run. There can be different resons
for this. One reason is that the “DTC Monitoring Test Conditions” stated at the DTC in the workshop manual is not
fulfilled during the DTC read-out. Another reason could be if the component/sensor/function is not valid or used by
the application where the read-out takes place.
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 00 - GENERAL

In this example the read out was made on a not running engine. A check in the manual for this DTC shows that not all
the “DTC Monitoring Conditions” have been met.
The conditions states that:
Engine Coolant Temperature at engine start must be
below 60°C
AND
Barometric Pressure within limits
AND
Engine must be running
AND
Engine must be warmed up to operating temperature. If
not all of these conditions are met the diagnostic moni-
toring will not run.

Since the Engine Running condition is not true the diag-

nostic monitor has not run and P01152A is then “Unde-
fined”.

P01152A
Engine Coolant Temperature Sensor 1
SPN [FMI]: 110 [10]
Node: EMS
FTB Name: Signal Stuck In Range
Lamp Status: Yellow alarm status
DTC Monitor Detection Time: 120 seconds
DTC Monitor Test Condition: Coolant Temperature at engine start below 60 °C
and
Barometric Pressure between 83 and 120kPa
and
Engine running
and
Engine considered to be fully warmed up.

If the DTC previously had “Active” status and then was “Cleared” (using VODIA), the repair is not verified since the
DTC Monitoring Test has not been performed (DTC status is “Undefined”).
Only when a DTC has “Verified OK” as status the repair can be considered verified.

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00 - GENERAL

This DTC read out on a TAD1380VE engine can be a bit confusing to interpret since this engine does not have any
of the exhaust temperature sensors that are mentioned in the read out. Why they do occur during this DTC read out
are because they exists in the ECU software even if they are not used by this engine model and could never become
active DTCs.
In this example the “Undefined” status for these sensors is logical since they are not used and that the diagnostic
monitor has not run. In some cases “Verified OK” will be shown even if a sensor is missing. That can happen since the
diagnostic monitor, in this case for high/low exhaust temperature, has not reported any fault.

Be sure to know what sensors and components that are applicable on the application you work with otherwise some
DTCs statuses can seem strange.

Validate repair using DTC status

A VODIA DTC read out can be filtered by selecting which statuses that are of interest. A selection of all statuses will
present all available DTCs that are contained in the software of an ECU. This will present a huge number of DTCs.
Better is to first see if any “Active” or “Inactive” DTC is stored. Then after repair done, get confirmation that the “Ac-
tive” status has changed to “Verified OK”.

1. Only read out “Active” and “Inactive” DTCs.

2. Repair the fault that triggered a DTC.
3. Perform a read out of all DTC statues from the fault setting ECU.
4. Verify the repair by checking that the DTC has changed status from “Active” to “Verified OK”.
5. If status has changed from “Active” to “Undefined” check the DTC Monitor Test Condition in the DTC workshop
manual for the DTC and make sure those are fulfilled before performing a new read out.

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 21 - ENGINE

21 - Engine

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21 - ENGINE

Relative Compression Test

Description
It is possible to perform a “compression” test on an en-
gine by using VODIA.
This test is an inbuilt function in the engine control unit.
VODIA is only starting/activating the test and, when the
test is done, collects data from the engine control unit The Compression test is available in VODIA.
and present it.

The test will not present information about the actual

compression status of the cylinders, only present an
indication of the relative “compression” status between
the cylinders.

Routine Description
The test is measuring the momentary engine speed fluctuation during cranking of the engine. The fluctuation is mea-
sured by calculating the acceleration between where maximum compression occurs and where maximum expansion
occurs for each cylinder. Fuel injection is disabled during testing.
The test result is presented in form of percentage values per cylinder where the largest acceleration is considered to
have the highest compression. The cylinder which was calculated to have the highest acceleration during the mea-
surement is set to 100%. The other cylinders values are set in relation to that. A cylinder presented with 90% “com-
pression” has not 10% lower “compression” than the one with 100%.
To take into consideration is when a cylinder is performing “bad“ (show a low percentage) it will affect the result of
the other cylinders that comes next in firing order.

• The engine should if possible be warmed up before running the test. The test result will be more stable on a
warmed up engine.
• The test should, in some cases, be run several times to give any valid information. If cranking a cold engine the
piston rings will not perform at their best the first run and the test result can therefore be very poor. It can be a
huge difference at later runs as will be shown in an example.
• When performing the test be sure to have good batteries at hand since multiple cranking efforts will drain
power. In the test the battery condition is monitored before the test can be started. If too low battery voltage is
detected the test can´t be started.

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To illustrate how the result from a compression test will change when the test is run several times, plotted results from
three, after eachother performed, tests are shown.
A TAD870 engine with 2000 running hours and no faults was used and the test was performed at room temperature.

The plotted red line in the graphs at 40% indicates the level at which the test will change the evaluation for a cylinder
from “OK” to “Not reliable”. “Not reliable” does not necessary mean that a fault is detected but that something needs
to be further investigated or that more test runs needs to be performed.

1st run
The first run states that cylinder 6 status is evaluated
“Not reliable” in comparison to cylinder 1 since that it
is set to be 100%. Looking at the other cylinders their
values are distributed somewhere in between. At this mo-
ment no conclusions can be drawn. Is cylinder 6 running
very smooth or is cylinder 1 running very hard?

2nd run
The second run differs a lot from the first one. Now cylin-
der 6 is evaluated “OK”, it has gone from 35% to >50%,
and the difference from the “best” to the “worst” cylinder
has shrunk. This because of that the friction heat from the
cranking cycles is making the piston rings work better.

3rd run
The third run of the “compression” test show higher
values for cylinder 5 and cylinder 6 compared to the
second run. Cylinder 3 has the lowest value, 70%, this
test round.
There are no faults detected “compression” wise on this
engine.

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21 - ENGINE

The picture shows how a test result could look in VODIA.

The result on this particular engine shows that there are
no problems when it comes to the relative compression
between the cylinders.

Conclusion
The conclusion after three runs is that the relative compression between all cylinders on this particular engine looks
good.

• The test is to be used when fault tracing an engine with symptoms/problems that could be related to the
compression of the engine.
• During test result evaluation it is important to know what engine symptoms/problems that exists.
• When testing always look for tendencies between all runs before making any conclusions.

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 23 - FUEL SYSTEM

23 - Fuel system

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23 - FUEL SYSTEM

Injector Test
Description
The injector test can be used to check whether one of the
injectors, in comparison to all the others, deviates in the
amount of fuel it delivers. This information can be useful
when troubleshooting engine performance issues such as
The Injector test is available in VODIA.
uneven running, rough idle, hesitation, lack of power, high
exhaust temperature, etc.
VODIA Injector Test is available on:
• D4/D6 with EMS

Routine Description
The injector test utilizes an in-built engine control unit • When starting the test there is a minimum coolant
function, cylinder balancing. Cylinder balancing as such is temperature condition that will be checked. This be-
not a functionality that is activated during normal running cause the engine temperature must be high enough
of any Volvo Penta engine but the function is temporary to ensure reliable test values.
activated during the injector test. What the cylinder bal- • When the test is started, check that the engine speed
ancing function does is to smoothen the engine running is stable at approximately idle speed.
at idle. This is achieved by individual compensating the • Monitor the “Fuelling Offset Ratio” data for all injec-
amount of fuel delivered by each injector. The individual tors. Continuously make an evaluation of the offset
compensating, a fuelling offset ratio, for each injector can values. The offset value for each injector can alter
be positive or negative. between positive and negative values during the test.
This is normal.
• After the test is stopped, make sure that “Reset
A positive offset ratio value means that the injection time Cylinder Balancing Value” routine has been executed,
is increased. checked green by VODIA. The routine should auto-
matically be performed when the test is stopped.
A negative offset ratio value means that the injection time This is very important because otherwise the offset
is decreased. values obtained during the test will be set in the
engine control unit which will affect the engine per-
formance negative during normal running. If, for any
Some injectors will show a positive offset ratio while at reason, there is any doubt that the offset values been
the same time some injectors will show a negative offset reset correctly run the “Reset Cylinder Balancing
ratio. This is normal in order to make the engine run as Offset” routine using VODIA.
smooth as possible.

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Test Example
During the test the offset values will change continously.
The offset value could alter between negative and pos-
itive values for the same injector during the test. This is
normal during actived cylinder balancing.

The picture shows an example view how the result is

presented after the injector test session been stopped by
the user. During this test run there were no obvious dif-
ferences between the offset values and none of the offset
values did stabilize at a high negative or positive value.
This indicates that all injectors are ok.

Notice the green checked “Execute Reset Cylinder

Balancing Offset Value” sentence at the bottom of the
VODIA view.

If a “Fuelling Offset Ratio” reach a value of 100% it

implies that that injector/cylinder needs further examina-
tion.

In this example injector 2 deviates when compared to all

other injectors. Since injector 2 is positively compensat-
ed, more fuel added, it means that cylinder 2 is not pro-
viding enough torque (compared to the other cylinders)
during normal running.
In this test case a faulty injector was used.

The test result also shows that because of the faulty in-
jector other fuelling offset values also deviates from what
would be expected. This is normal when having a large
offset value deviation since all injectors/cylinders influ-
ences eachother. Always investigate the injector/cylinder
that have the largest deviation.

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If there is an injector which offset value differ compared to the others is does not necessary means that the injector is
faulty. For example a cylinder with less compression compared to the others will also be fuel compansated so for an
accurate evaluation it is important to conduct further tests. Other valid tests to perform would be the “Relative Com-
pression Test” and the “Injector Cut-out Test”.

The injector test is to be used when fault tracing an engine with symptoms/problems that could be related to the
fuel system.
During test result evaluation it is important to know what engine symptoms/problems that exists.
A large offset deviation does not single out a faulty injector but that a cylinder is not performing for what ever
reason.
The Relative Compression Test and the Injector Cut-out Test could provide useful information.

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 25 - INLET & EXHAUST SYSTEM

25 - Inlet & Exhaust system

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eEPG, check
A fully functioning EPG will have a working range from completely open to completely closed. If the valve is not func-
tion properly it will affect the exhaust temperature.

Fault symptom
If the valve position can’t be regulated properly during a regeneration session the correct exhaust temperature will not
be reached and the regeneration session will be aborted.

To check the EPG function:

1. Remove the exhaust system.
2. Use VODIA service routine: “eEPG Position Test” to test the function of the EPG.
3. Request 100% valve position. [0-100% (open-close)]
4. Visually inspect the valve position during the test.

This EPG is not closing properly and needs This EPG is closed properly.
to be replaced.

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Preheat Relay, check

Description
The preheat relay is mounted on the engine and controls the power provided to the heating element. The relay con-
sists of a microcontroller that controls the status of power MOSFET drivers. The electronics in the relay is over cur-
rent and over temperature protected.

Preheat activation condition

If the preheat function can be activated depends of the temperature of the coolant temperature and the oil tempera-
ture. The EMS will use the lowest of these temperatures and check if the preheat function shall be activated. If any of
the temperatures is lower than the calibrated trigger value the preheat relay is activated. The preheat activation time
depends of the trigger temperature and of the ambient pressure. Different engine models have different settings but
in general the preheat function is activated from 0°C for 3-5 seconds and up to 35-50 seconds at -25°C (at sea level).

The preheat relay on/off status is controlled by the EMS pin B25. When the EMS requests an activation of the pre-
heat relay, B25 a low side driver will change from high to low (Vbat+ to 0V), current will flow through the relay from
“VBat in” to “V out” to the heating element. At the heating element the EMS senses, pin B7 changes from low to high
(0V to 0.8*Vbat+), that the relay has been activated.

Preheat request B25 B7 Heating element

off Vbat+ 0V off
on 0V 0.8*Vbat+ on

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Wastegate Valve, check

Description
The wastegate valve is a PWM controlled 3 way 3 posi-
tion valve.
To check the function of the valve pin 2 (PWM input)
must be grounded to pin 7. When pin 2 is grounded the
valve will for a moment change position, a click is heard,
then change back to its start position. Since this is a
PWM controlled valve a frequency of the input signal
at pin 2 must be added to make the valve change and
hold its position. This is done manually by grounding/not
grounding.. etc. the signal at pin 2.

Special tools
88890053 Brake-out cable

1. Connect break-out cable 88890053 to the waste-

gate valve.
2. Connect a 24 voltage power supply between pin 1
and pin 7.
3. Connect a test wire at pin 2.
Simulate a PWM signal by grounding/not ground-
ing...etc. the test wire at pin 7.
4. Blow in connection 21 while testing the valve. The
air flow will alter between P1 and 31 when the valve
change its position.

Wastegate Pin Wastegate Connections

1 Vbat+ P1 Supply
2 PWM Input 21 Delivery
7 GND 31 Exhaust

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SCR NOx Conversion Test

Description
The NOx sensor and SCR NOx conversion test routine
is taking control of demanded engine out NOx, EATS
heating, engine speed and urea dosing in a sequence of
different levels that provides a diagnostic self test re-
The NOx Conversion Test is available in VODIA.
sult on the main functionality of the EATS system. By a
number of predefined steps, phases, it evaluates the NOx
sensors’ capability of, and accuracy in, reading high and The NOx Conversion Test is available on:
low NOx levels, and that correct conversion efficiency is • TAD58x, TAD88x, TAD118x, TAD138x
achieved while dosing urea.
During the run of the routine there will be several routine
responses that are evaluated and presented in the AM
tool.

• The routine can only be used on engines that are

permitted to run at 1900rpm.
• The routine is calibrated to work at sea level.
(Patm. 95-105kPa). If used at higher/lower altitude
the NOx evaluation within the routine will fail.

Exhaust system layout

T1 = Exhaust temperature sensor 1, pre DOC N2 = Outlet NOx sensor

T2 = Exhaust temperature sensor 2, pre DPF P = DPF differential pressure sensor
T3 = Exhaust temperature sensor 3, post DPF DM = Dosing module
N1 = Inlet NOx sensor

The picture shows a principal layout of an aftertreatment exhaust system. The system contains of a diesel oxidation
catalyst (DOC), diesel particulate filter (DPF), selective catalytic reduction catalyst (SCR Cat) and a ammonia slip cat-
alyst (NH3 Cat). For monitoring and controlling the system different sensors and an actuator (DM) are connected to it.

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NOx Conversion Routine Parameters

When running the SCR NOx conversion test routine there are several parameters that can be viewed in VODIA.

• Engine Coolant Temperature

• Engine Speed
• Exhaust Gas Temperature Bank 1
The Exhaust Gas Temperature Bank 1 consists of 4 different parameters where sensor 1-3 are the ones that are
used and monitored:
Exhaust Gas Temperature Bank 1, Sensor 1 (= T1, pre DOC)
Exhaust Gas Temperature Bank 1, Sensor 2 (= T2, pre DPF)
Exhaust Gas Temperature Bank 1, Sensor 3 (= T3, post DPF)
• Selective Catalytic Reduction NOx Conversion Monitor - Information
This parameter contains routine test status and routine result parameters.
• Current AdBlue Mass Flow
• NOx Conversion Efficiency
• NOx Sensor
This parameter contains both inlet and outlet NOx parameters:
NOx Sensor Concentration Bank 1 Sensor 1 = NOx Inlet sensor, N1
NOx Sensor Concentration Bank 1 Sensor 2 = NOx Outlet sensor, N2

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Routine Start

The SCR NOx conversion test routine consists of 4 different evaluation phases:
1. SCR heating phase.
2. NOx sensor high and low level evaluation.
3. NOx conversion efficiency evaluation.
4. NOx sensor zero level evaluation.

Start

SCR Heating
Phase

NOx Sensor
High and
Low Level
Evaluation

NOx Conversion
Efficiency
Evaluation

NOx Zero
Level
Evaluation

End

Before the test routine is started some preconditions are checked by the routine:
• That engine is running
• Battery voltage status
• DTC status
• DPF soot load
• etc.

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SCR Heating Phase

SCR heating phase is used for starting up/activate the NOx sensors (remove any moisture that will damage the sen-
sors) and to ensure that the SCR is heated up (when reaching specified operation temperature the NH3 (ammonia)
buffer of the catalyst is empty). A filled NH3 buffer may otherwise set false faults on the NOx outlet sensor, or suggest
too big difference between inlet and outlet NOx sensors.

Start
At this phase the:
• EGR is closed.
• EPG is closed.
• Engine speed is increased to 1400 rpm. SCR Heating
• Fuel injection timing is altered. Phase
• Rail pressure is altered.

- No dosing is occuring during this phase.

NOx Sensor
High and
Low Level
Evaluation

NOx Conversion
Efficiency
Evaluation

NOx Zero
Level
Evaluation

End

During the SCR heating phase the NOx sensors signal quality are monitored. When the signal quality for each sen-
sor is evaluated as “Good” the sensor output will start to show a ppm value. The NOx inlet sensor will under normal
circumstances reach the state “Good” before the NOx outlet sensor.
If the system is already heated and both NOx sensors are evaluated “Good” a minimum time, 300s, must elapse be-
fore continuing to next phase because of emptying the SCR of NH3.

The SCR heating phase is fulfilled when the SRC average temperature is above 330 degrees and held for a calibrated
time and both NOx sensors signal quality are evaluated as “Good”.
Inlet and outlet values and should follow eachother and will show about 1000ppm during this phase. However the
NOx outlet value could initially show a much lower value than the NOx inlet value before the SCR buffer is emptied.
But if the NOx outlet value never rise up to approximately the same level as the NOx input value this could indicate
that there is a crystal in the system.

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Fault is reported if:

• SCR temperature is not reached within specified time of intence heating. Max time 1800s.
• Not both of the NOx sensors responds with “Good” quality.

Reason for failing the test could be:

• Exhaust leakage.
• Crystal build up at T3. If crystal build up at T3, T3 will show much cooler exhaust temperature than T1 and T2.
• Fault in any of the exhaust temperature sensors.
• Fault in any of the NOx sensors.

An example of all Exhaust temperature sensors during a normal heating phase.

Green = T1, Exhaust temperature sensor 1, pre DOC
Yellow = T2, Exhaust temperature sensor 2, pre DPF
Red = T3, Exhaust temperature sensor 3, post DPF

An example of all Exhaust temperature sensors during a complete routine run.

Green = T1, Exhaust temperature sensor 1, pre DOC
Yellow = T2, Exhaust temperature sensor 2, pre DPF
Red = T3, Exhaust temperature sensor 3, post DPF
Pink = Indicates the different phases/states of the NOx Conversion routine

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NOx High Low Level

During the NOx high and low level evaluation phase the functionality of both NOx sensors are checked, when the en-
gine is producing as high NOx and as low NOx as possible. This is done by altering fuel injection timing, engine speed,
rail pressure.

At this phase the: Start

• EGR is altered between closed or open.
• EPG is altered between closed or open.
• Engine speed is altered between 700 and
1100 rpm.
• Fuel injection timing is altered. SCR Heating
• Rail pressure is altered Phase

- No dosing is occuring during this phase.

NOx Sensor
High and
Low Level
Evaluation

NOx Conversion
Efficiency
Evaluation

NOx Zero
Level
Evaluation

End

At this phase the Inlet and Outlet NOx values are compared (expected NOx levels must be reached within a given
time frame) and should follow eachother. Each of the low and high evaluations will be performed 2 times. Firstly
low NOx is tested and there after high NOx. Since there is no conversion taking place, no dosing, the sensors values
should read roughly the same for in and out NOx. If there is a significant difference between in and out NOx sensors
values (high inlet NOx and low outlet NOx) it can indicate that there is a crystal in the system.

The evaluation of this test phase checks:

• That when the engine is in low NOx mode, low NOx is read by both sensors.
• That when the engine is in high NOx mode, high NOx is read by both sensors.
• That the difference between the sensors in low and high NOx mode is not too large.

If any of the different NOx evaluation phases fails the test will set “Not Reliable”.

A fault is reported if:

• Any of the NOx sensors fails to read both low and high NOx.
• There is a difference between the inlet and outlet sensor that is greater than a fault limit.

Reason for failing the test could be:

• Exhaust leakage.
• EGR pipe leakage.
• Fault in any of the NOx sensors.
• A crystal in the system.
• High altitude (low NOX test will fail in high altitude)
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NOx Conversion Efficiency

During the NOx conversion efficiency evaluation phase the engine will start dosing urea when producing as much
NOx as possible. The amount of urea injected should be sufficient to reduce out NOx to almost zero. A NOx conver-
sion efficiency is calculated and must be above a calibrated threshold value for a calibrated time.

Start

SCR Heating
Phase

NOx Sensor
High and
Low Level
Evaluation

NOx Conversion
Efficiency
Evaluation

NOx Zero
Level
Evaluation

End

A fault is reported if:

• The NOx conversion efficiency is below a threshold value of 70%.

Reason for failing the test could be:

• Low dosing valve performance or faulty dosing valve.
• Faulty/aged SCR

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NOx Zero Level

During the NOx zero level evaluation phase, fresh air is fed into the exhaust system by first increasing the engine
speed to 1900rpm and then cut off fuel supply. The purpose is to evacuate all remaining exhaust gases and replace
them with clean air. Both NOx sensors are expected to read close to zero values. The zero NOx test fails if there is a
significant difference between the inlet and outlet NOx sensor during the increased engine speed prior to the fuel cut
or if the measured NOx values exceed their limits after the engine has stopped.
Inlet NOx sensor value will decrease more rapidly than the outlet NOx sensor value. How fast the outlet NOx sensor
value decreases depends of how easy/difficult the exhaust system is to ventilate.

Start

SCR Heating
Phase

NOx Sensor
High and
Low Level
Evaluation

NOx Conversion
Efficiency
Evaluation

NOx Zero
Level
Evaluation

End

A fault is reported if:

• If any of the Inlet and Outlet NOx sensor values does not fall below:
Inlet NOx = 20 ppm, Outlet NOx = 150 ppm.

Reason for failing the test could be:

• The exhaust system is difficult to ventilate within the calibrated time frame. Verify that a correct installation of the
exhaust system been made.
• Fault in any of the NOx sensors.

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Routine Response
When running the routine the different response evaluations are presented with “OK”, “Not Tested” or “Not Reliable”.
Before the response is tested it shows “Not Tested”. During a routine phase a response can be evaluated as “Not
Reliable” before the routine phase has ended and there after be set to “OK” if all conditions were met. If there are
conditions that are not fulfilled the response will be set to “Not Reliable” and the routine will be aborted.
Use the “Routine Response Flow Chart” to assist when troubleshooting a failed routine respons.

Routine Phase Routine Response Evaluation

SCR heating phase
None
at engine speed = 1400rpm
NOx sensor low evaluation Inlet NOx Low Response
at engine speed = 700rpm Outlet NOx Low Response

Inlet Lambda Low Response

Inlet NOx High Reponse
Inlet NOx Rationality Response, (both low and high evaluation must
NOx sensor high evaluation be OK)
at engine speed = 1100rpm Outlet Lambda Low Response
Outlet NOx High Reponse
Outlet NOx Rationality Response, (both low and high evaluation
must be OK)

NOx conversion efficiency evaluation (urea

dosing) Urea Efficiency Response
at engine speed = 1100rpm
Inlet NOx Zero Response
NOx sensor zero level evaluation Inlet Lamda High Response
at engine speed = 1900rpm then a fuel cut. Outlet NOx Zero Response
Outlet Lambda High Response

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NOx Interpretation
Both pictures show Inlet (light blue) and Outlet (yellow) NOx levels at all different routine phases.

Heating Low High Low High Urea Zero

NOx NOx NOx NOx dosing NOx
Light Blue = NOx In level
Yellow = NOx Out level
Pink = Indicates the different phases/states of the NOx Conversion routine

No Fault
On a normally functional application, the Inlet and Outlet NOx levels will follow close to eachother up to the phase
when dosing of urea starts to occur. At this phase the Outlet NOx will drop to almost zero. At the last phase, when the
engine is ventilated, both Inlet and Outlet NOx levels will drop to close to zero.

Light Blue = NOx In level

Yellow = NOx Out level

Crystal
In this example the difference between Inlet and Outlet NOx levels is too large in the heating phase, the first low NOx
phase, the first high NOx phase, the second low NOx phase.
In the second high NOx phase the levels are as expected during a high NOx phase evaluation. This indicates that there
was a crystal in the system when the test routine is activated. The crystal dissolves during the routine and therefore
lower the Outlet NOx even when no dosing is occuring.

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Routine Response Flow Chart

NOx conversion test routine consists of 4 different During the routine, “Test Status” in VODIA shall be monitored
phases: where there is info about::
1. SCR heating phase. NOx Sensor Start Status
2. NOx sensor high and low level evaluation. NOx Quality Status
3. NOx conversion efficiency evaluation. Phase Status
4. NOx sensor zero level evaluation. SCR Operating Temperature Status
Urea Dosing System Status
To achieve a reliable routine result make sure that Urea Injection Demand Status
the following is checked ok:
Start
- AdBlue/DEF quality
- Dosing valve performance
- No leakage in the exhaust system
Preconditions=true

Phase Status=
SCR Heating

SCR Heating NO
1
Phase Passed? (Test Routine Aborted)

YES

Phase Status=
NOx Sensor
High and Low
Level
Evaluation

NOx Sensor High and

NO
Low Level Evaluation 2
(Test Routine Aborted)
Passed?

YES

Phase Status=
NOx Conversion
Efficiency
Evaluation

NOx Conversion
NO
Efficiency Evaluation 3
(Test Routine Aborted)
Passed?

YES

Phase Status=
NOx Zero Level
Evaluation

NOx Zero Level NO

4
Evaluation Passed? (Test Routine Aborted)

End

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SCR Heating Phase

1
When reached high enough exhaust temperature, within a time limit, the NOx sensors
should respond with:
NOx In Sensor Started, OK
NOx In Quality Good, OK
1. Check that there is no leakage anywhere in the
exhaust system., pipes, muffler, connections
NOx Out Sensor Started, OK
(clamp), dosing valve, etc. NOx Out Quality Good, OK
2. Verify that the exhaust system complies to the
installation instructions (pipe length, pipe SCR Operating Temperature Status should respond with SCR Operating Temperature
diameter, radius, etc.) Reached, OK.
Compare T1, T2, T3 exhaust temperature sensors output during the heating phase. All
OK sensors (T1, T2, T3) should show >330° at the end of the heating phase.

YES
1. Check all wiring and connectors to the NOx sensor.
Is Execution Status: (NOx In Quality
2. Replace the Inlet NOx sensor.
"Inlet NOx quality not reliable"? Compromised OR NOx In
3. Re-run the test routine.
Sensor Not Started,)

NO
(NOx In Quality Good, OK AND NOx In Sensor Started, OK)

1. Check all wiring and connectors to the NOx

Is Execution Status:
sensor.
"Inlet lambda quality not YES
2. Replace Inlet NOx sensor.
reliable"?
3. Re-run the test routine.

NO

YES 1. Check all wiring and connectors to the NOx

Is Execution Status:
(NOx Out Quality sensor.
"Outlet NOx quality not
Compromised OR NOx Out 2. Replace Outlet NOx sensor.
reliable"?
Sensor Not Started, ) 3. Re-run the test routine.

NO
(NOx Out Quality Good, OK AND NOx Out Sensor Started, OK)

1. Check all wiring and connectors to the NOx

Is Execution Status:
sensor.
"Outlet lambda quality not YES
2. Replace Outlet NOx sensor.
reliable"?
3. Re-run the test routine.

NO

YES
Is Execution Status:
(SCR Operating
"Heating state failed to reach
Temperature
target SCR temperature"?
Not Reached )

Are all exhaust

1. Check that all exhaust
temperature sensors
NO temperature sensors are connected
connected correctly NO
(SCR Operating Temperature Reached, correctly.
and to the right
OK) 2. Re-run the test routine.
connector in the
wiring harness?

End
YES

Is T3 >330 °? YES 1. Re-run the test routine .

NO

1. If T3 shows much less temperature than T2 remove the T3 sensor and check for crystal
build up. Remove any crystal build up. If no crystal build up is detected, replace T3
sensor.
2. Check that the EPG is fully functioning. The EPG should be closed during SCR Heating
Phase.
If T1 and T2 > 330 during the heating phase the EPG is ok.
3. Re-run the test routine.

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NOx Sensor High and Low Evaluation

During this evaluation phase analyze/monitor the reading of both Inlet and
Outlet NOx sensors.

Low NOx Evaluation phase = Engine Speed 700rpm

High NOx Evaluation phase = Engine Speed 1100rpm

1. Check that the fuel used fulfills Volvo Pentas

specifications.
2. Check that there is no leakage anywhere in the exhaust
system., pipes, muffler, connections (clamp), dosing valve,
etc.
3. Check the EGR pipe for leakage.
4. Verify that the exhaust system complies to the installation
instructions (pipe length, pipe diameter, radius, etc.).

If both NOx sensors fail in High NOx evaluation the reason is most probably
that the engine is not producing enough NOx.
Is Execution Status:
YES
"Engine out NOx If the engine is not producing high enough NOx:
(Inlet AND Outlet
failed to reach target 1. Check the charge air system for leakage.
NOx<800ppm)
level"? 2. Ckeck that the fuel quality used fulfills Volvo Pentas specification.,
3. Check that the EGR is fully functioning. EGR should be closed during "SCR
Heating Phase/High NOx mode".

NO

"If both Inlet and Outlet Low Response = Not Reliable:

Check if EGR is blocked or has an electrical malfunction."

Is "Inlet NOx Low Response"

1. If only one Low Response = Not Reliable:
or "Outlet NOx Low YES
Replace:
Response" = Not Reliable?
Inlet NOx sensor if "Inlet NOx Low Response"=Not Reliable.
Outlet NOx sensor if "Outlet NOx Low Response"=Not Reliable.
3. Re-run the test routine.

NO

"If both Inlet and Outlet High Response = Not Reliable:

Check if EGR is stucked open"
YES
Is "Inlet NOx High Response"= Not Reliable?
(Inlet NOx<800ppm)
1. Replace the Inlet NOx sensor.
2. Re-run the test routine.

NO

"If both Inlet and Outlet High Response = Not Reliable:

Check if EGR is stucked open"

YES
Is "Outlet NOx High Response"= Not Reliable? 1. Remove the Inlet NOx sensor and check for crystal build up.
(Outlet NOx<800ppm)
Remove any crystal build up and re-run the test.
1. Replace the Outlet NOx sensor.
2. Re-run the test routine .

NO

The difference between Inlet and Outlet sensors is too

Is Execution Status: large. They should show roughly the same.
"Inlet NOx Rationality YES
Response" or "Outlet NOx (Diff>100ppm at low NOx OR 1. Verify that the exhaust system complies to the
Rationality Response" = Not Diff>200ppm at high NOx) installation instructions (pipe length, pipe diameter,
Reliable? radius,NOx sensors placement, etc.).
2. Replace the most likely faulty NOx sensor.

NO

End

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NOx Conversion Efficiency

During this evaluation phase analyze/monitor:

Current AdBlue Mass Flow
NOx Conversion Efficiency
Inlet NOx Sensor
Outlet NOx Sensor
3

Is "Urea Efficiency Response = Not Reliable"? NO End

YES
(NOx Conversion
Efficiency < 70%)

1. Check that the urea used fulfills Volvo

Pentas specifications.
2. Perform the "Urea Dosing Test" in AM tool.
Be sure to cover both small and big volume
test .

Are both measured volumes,

small and big, within expected YES 1. Check the SCR muffler .
volumes?

NO

1. Check that there is no leakage or restrictions in the

system.
2. Check that the correct dosing valve is installed.
3. Change the pump filter and check that the strainer in
the inlet connector at the pump is clean. (If the system
needs to be cleaned, refer to the workshop manual)

Re-run the test after any action

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NOx Sensor Zero Level Evaluation

During this evaluation phase analyze/monitor:

Inlet NOx Sensor
Outlet NOx Sensor
4

1. Check that the exhaust system fulfills Volvo Pentas specifications.

Check for restrictions that could prevent the exhausts to be properly
vented.

Is "Inlet Lambda High

Response" or
YES 1. Replace the Inlet NOx sensor.
"Inlet NOx Zero
(Inlet NOx > 20ppm) 2. Re-run the test routine.
Response" = Not
Reliable?

NO

Is "Outlet Lambda High

Response" or YES 1. Replace the Inlet NOx sensor.
"Outlet NOx Zero (Outlet NOx > 150ppm ) 2. Re-run the test routine.
Response" = Not Reliable?

NO

End

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Crystal Inspection
Description
In all after treatment systems that uses an aqueous solution as AdBlue/DEF there are going to be minor crystal de-
posits within the system. A crystal deposit in it self is not a sign of a fault in the after treatment system. The amount of
crystal deposit within the system will change over a drive cycle and is depending of the exhaust temperature i.e how
the engine is used.

If a fault occurs in the after treatment system a larger crystal deposit than “normal” could arise. This crystal deposit is
a symptom that indicates that the system needs to be checked. What decides a “normal” or “unnormal” sized crystal
deposit is decribed in the Crystal Size Guide.

Crystal Symptoms
Symptoms that could indicate a larger than normal crystal within the after treatment system are:
• Poor NOx conversion (will set a DTC)
• Lower than expected temperature from Exhaust Temperature Sensor 3 (only valid for stage 5. Will set a DTC).

A crystal is not the only thing that can cause these symptoms so a troubleshooting accordingly to the workshop
information available for any DTCs should be performed as a first step.

Any crystal deposit outside of the exhaust system indicates that there is a leakage in the exhaust system. The outside
crystal deposit must to be removed and the exhaust system needs to be checked.
1. Remove the exhaust pipe and clean it with hot water. Do not use high pressure cleaning on the complete system.
High pressure cleaning is only allowed on piping that been removed.
2. Inspect the inside of the exhaust pipe and the pipe connectors/flenses. All crystal deposit should be removed.
3. Change all affected gaskets. Reassembly the exhaust system accordingly to the workshop manual.
All clamps are not allowed to be reused. Check the workshop manual for information.

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Before checking for crystal deposit perform the “SCR Crystal Remove” option located within the “Regeneration
(EATS Cleaning)” operation in VODIA.

Crystal Size Guide

There are two different SCR systems that are used for stage 5 engines. When checking for any crystal deposit follow
the steps for the correct SCR system. For other emission legislations such as 4F and IMO3 the exhaust systems are
different but the crystal size guide could still be used.

1. Remove the dosing valve and do a visual inspection into the mixing chamber.
- Some crystal deposit is ok.
- A thin layer of crystal (~1 mm) is ok and doesn´t need to be removed
2. Remove the mixing chamber and do an inspection of it.
- Some crystal deposit is ok. A crystal, approximately the size of a chickens egg, is ok.
- A thin layer of crystal (~1 mm) is ok and doesn´t need to be removed.

1. Remove the exhaust pipe between the DPF and the SCR. Do a visual inspection to-
wards the dosing valve and towards the SCR inlet.
- Some crystal deposit is ok. A crystal, approximately the size of a chickens egg, is ok.
- A thin layer of crystal (1 mm) is ok and doesn´t need to be removed.

A thin layer of crystal deposit doesn´t need to be removed.

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A thicker crystal layer or a large crystal deposit must to be removed.

After removing any large crystal deposit the VODIA operation “Urea Adaptation Reset” must be performed.
This will reset the dosing adaption strategy in the EMS.
After the deposit is removed the “SCR Nox Conversion Test” can be used to check the system status.

Reasons for large crystal deposit

There are different reasons why a larger than normal crystal can occur. The main reasons are either too low average
exhaust temperature or too large quantity of urea injected.
• Leakage in the mixing pipe/clamps between the DPF and SCR. (The exhaust temperature is affected)
• Insufficient insulation of exhaust system. (The exhaust temperature is affected)
• Malfunctioning dosing valve. The dosing valve is leaking urea into the exhaust system.
(The urea quantity is affected)
• EGR malfunctioning. (The exhaust temperature is affected)
• Oversized charge air cooling system. (The exhaust temperature is affected)

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Silencer/SCR Inspection
Before replacing the silencer/SCR unit in the after-treatment system as a repair
action it is important to inspect the silencer/SCR unit to check for the reason of why it needs to be exchanged. If the
silencer/SCR unit been contaminated the root cause of the contamination must be found before any silencer/SCR
replacement.

A silencer/SCR unit replacement could be necessary depending of different reasons:

- Worn out/normally aged - Clogged (DPF/DOC)
- Mechanical damaged - Crystallization
- Corroded - Melted/cracked (DPF/DOC)

Before replacing the the silencer/SCR unit following steps shall be performed:
1. Perform a regeneration using VODIA.
2. Run the SCR NOx Conversion Test routine and interpret the result.
3. Perform a Crystal Inspection.
4. Perform a DPF Inspection.
Analyzing the status and condition of the components inside of the silencer/SCR unit is difficult. Instead do a vi-
sual inspection of the DPF. Examine the condition of the filter and see if a root cause of why the silencer/SCR unit
is not functioning correctly can be found. Use the example pictures for comparison to see if there is any resem-
blance with the examined filter.
Check filter and silencer piping for:
- Oil residue (There shall not be any oil residue on the filter or in the silencer piping)
- Urea residue (There shall not be any urea residue on the filter)
- Excessive soot on the filter or in the silencer piping.
5. If no explicit root cause can be found when analyzing the DPF replace the silencer/SCR unit.

After a silencer/SCR replacement, run the VODIA “EATS Reset” operation. This to reset specific parameters in the
EMS that are used for calculating and optimizing the system.

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DPF = OK The images below shows DPFs that’ve been installed in fully functioning after-
treatment systems. These DPFs have been located in different applications with different condi-
tions such as running hours, engine load etc. There can be different levels of soot visible on a DPF
without there being a problem or fault in the system.

The DPF outlet/SCR inlet should be soot free in a normal

functioning after-treatment system.

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DPF = NOK The images below shows DPFs that are clogged due to faulty urea mixture being used.
Action: Replace the DPF and the silencer/SCR unit.

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DPF = NOK The images below shows a DPF and a DOC outlet that are contaminated with oil. In cases of con-
tamination the reason behind the contamination must be found before any replacement is done.
When analyzing the contamination reasons the DPF been contaminated due to a cracked piston.
The DOC been contaminated due to a faulty EGR.
Action: Replace the DPF and the silencer/SCR unit.

DPF = NOK The images below shows excessive soot in the DPF outlet/SCR inlet and at the DPF. In case of
excessive soot in the system the reason for it need to be investigated. Use the “Regeneration
Interruption Counters Readout” operation in VODIA to check if the regeneration function has been
interrupted and if so by what and how many times. When analyzing the reason for the excessive
amount of soot in this particular case a faulty EGR was discovered.
Action: Replace the DPF and the silencer/SCR unit.

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DPF = NOK The images below shows DPFs that have melted and a DOC that has cracked due to very high
temperature. A cracked or melted component is a secondary fault. The root cause must be found
before any replacement is done.
Action: Replace the DPF and the silencer/SCR unit.

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Regeneration
Description
The EMS continously calculates the need of a regeneration and informs the operator via the display when a regenera-
tion needs to be performed.
There are several criterias that must be met to perform a successful regeneration.

A regeneration request is activated for any of the listed reasons:

• High soot load in the DPF.
• High hydrocarbon (HC) load in the Diesel Oxidation Catalyst (DOC).
• Crystal deposit (this function is by default deactivated. Can be activated via a VODIA kit)
• High sulphur load.

Soot load
The EMS is using the DPF differential pressure to calculate the amount of soot in the filter.

Soot load between 60-80%: The operator can start the regeneration.
Soot load above 80%: VODIA must be used to start the regeneration.

A regeneration increase the engine speed to 1400rpm and during the regeneration the temperature inside the DPF
increases to ≈470⁰C. The regeneration last from ≈35 – 60 minutes depending on soot level.
Note: Low load during long periods will increase the soot load.

HC load
The HC load is calculated by the EMS.

A regeneration increase the engine speed to 1400rpm. The exhaust temperature increases to ≈350-400 ⁰C.
The regeneration last for ≈20min.
Note: Long periods of running at idle with low exhaust temperature, <175°C, will increase the HC load.

Crystal deposit
The crystal model in the EMS is deactivated by default. It can be activated in cases where confirmed reoccuring prob-
lems with crystal deposit been established. A VODIA kit is used to activate the function.

A regeneration increase the engine speed to 1400rpm and during the regeneration the exhaust temperature increases
to ≈470⁰C. The regeneration last for ≈60 minutes.
Note: See the Crystal Inspection chapter for more info.

Sulphur load
The sulphur model, calculated by the EMS, is based on fuel consumption and EATS temperature.

A regeneration increases the engine speed to 1400rpm and during the regeneration the EATS temperature increases
to ≈520⁰C. The regeneration last for ≈75 minutes.
Note: Sulphates are released at temperatures above 450⁰C therefore a regeneration will be requested if T1>450⁰C
for 300 seconds.

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Regeneration requirements
• During regeneration engine load must not exceed 40%. If this is exceeded the regeneration will be aborted.
• During regeneration engine speed must be kept steady. If the engine speed deviates too much the regeneration
will be aborted.

Regeneration sequence
• Engine speed is increased to 1400rpm.
• EPG is closed to increase the exhaust pressure. Exhaust temperature will rise to ≈350-400°C.
• EGR is closed to increase the exhaust mass flow.
• Intake throttle valve is opened to increase exhaust mass flow.
• When regeneration for soot or crystal deposit, fuel is injected to further increase the exhaust temperature to
≈470-490°C.

Troubleshooting an interrupted regeneration

• Check that the EPG is closing properly. (visually inspection during VODIA test routine)
• Check that the exhaust temperature sensors are not connected in the wrong order.
• Check the exhaust pressure sensor pipe for clogging. (where applicable)
• If there also are symptoms like, uneven running/idling, loss of power, check the EGR valve for sticking behaviour.

After 5 aborted or failed regenerations the EMS will lock the system. No further regenerations can be activated
without using VODIA.

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26 - COOLING SYSTEM

26 - Cooling system

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Fan Control Test

Description
The fan control test makes it possible to force the fan
speed by controlling the PWM signal to the fan clutch.
By first demanding a high fan speed and there after a
lower fan speed the functionality of the fan hardware is
checked. If the fan speed could be altered, the fan hard- The Fan Control Test is available in VODIA.
ware is ok.
The Fan Control Test is available on:
• TAD58xVE, TAD88xVE
(may require an EMS software update to
be available)

Test Sequence
1. Manually increase the Engine Speed to 1500rpm.
2. Request a “PWM Value Fan 1” percentage of 50%.
3. Notice the “Fan Speed Fan 1” value.
4. Re-run the test. To prevent the engine from unintentional overheating there is a time limit before the test can be
re-run.
5. Request a “PWM Value Fan 1” percentage of 80-100%.
6. Check that the “Fan Speed Fan 1” value increases from previous value.
7. Re-run the test. To prevent the engine from unintentional overheating there is a time limit before the test can be
re-run.
8. Request a “PWM Value Fan 1” percentage of 10-30%.
9. Check that the “Fan Speed Fan 1” value decreases from previous value.

Test Interpretation
If the Fan Speed is changing when requesting different PWM percentage values the fan control circuit and the fan
hardware is ok.

If the Fan Speed is not changing as expected:

• Check that the engine has the latest software. If the Visco fan been added as an accessory a conversion kit must
used.
• Check that the fan hardware is installed accordingly to the installation instructions.
• Check all wiring and connectors between the EMS and the fan/fan clutch.

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30 - ELECTRICAL SYSTEM

30 - Electrical system

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Smart Relay Module, check

Description
The Smart Relay Module, SMR, (engine main relay) is
an electronical controlled relay. The smart relay module
has replaced the conventional mechanical relay as engine
main relay on several engine models. The smart relay
module forms a holding circuit for the EMS power supply
at “Ignition On”.

SRM Pin description

1. Battery (-)
2. Hold demand from EMS
3. EMS power supply
4. EMS power supply
5. Battery (+)
6. Battery (+)

Special tools
88890016 Brake-out cable
9990014 Brake-out cable
9998699 Measuring box

Sequence Brake-out SRM 9998699 Expected Measured

EMS Pin Notes
cable Pin Pin# Value Value

If U≠Vbat:
1-5 10-14 U≈Vbat
1. Check the fuse and all
Main switch
88890016 - wiring and connectors
on
1-6 10-15 U≈Vbat between the main switch
and the SRM.
Ignition On
Main relay hold activated.
(“Batt
switched” 9990014 - A58 58-bat(-) U≈Vbat
Note! EMS Connector A
in wiring
is used.
diagram)
Ignition On
(“Batt Blue LED in SRM acti-
switched” 88890016 2-4 - 11-14 U≈Vbat vated.
in wiring (see “Note 1”)
diagram)
1-3 10-12 U≈Vbat Green LED in SRM acti-
EMS Power
88890016 - vated.
On 1-4 10-13 U≈Vbat (see “Note 2”)

EMS Power B57-B58 57-58 U≈Vbat Note! EMS ConnectorB

9990014 -
On B60-B58 60-58 U≈Vbat is used.

Note 1: At “Ignition On” EMS:A58 receives Vbat which activates the “Main Relay Hold” function in the EMS and
EMS:A8, a low side switch, activates a “Hold circuit” via the SRM (blue LED in SRM activated).

Note 2: After the “Hold circuit” is activated, EMS:B57 and EMS:B60 receives Vbat via the SRM (green LED in SRM
activated).

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Alternator Voltage Reducer, check

Description
To prevent over-charging of batteries the alternator volt-
age reducer will control the target voltage for the alter-
nator using a PWM signal. The duty cycle corresponds
to the target voltage. For the correct target voltage, alter-
nator “sense” must be connected to battery(+).

The alternator reducer is powered via the aux/multilink

connector. The power status is indicated by a green LED.
The alternator reducer will activate the activation/magnetisation and PWM output when the CAN message “Engine
Running” is recieved. The status is indicated by a yellow LED.

1. Ignition On -> Interface powered via aux bus

2. Engine Running -> Activation/magnetisation of alternator & PWM output active
9998699 Measuring box
Special tools 88890074 Multimeter
88890016 Break-out cable

Green LED
On The unit has power.
Off No power.

Yellow LED
LED Indication
Constant lit No communication (AUX/Multilink) available.
Communication (AUX/Multilink) available.
1 Hz
No Engine running signal recieved.
Engine running signal recieved.
4 Hz
PWM output active.

Check AUX bus

1. Main switch Off.
2. Connect 88890016 between alternator reducer AUX connector and aux connector.
3. Main switch On.
4. Ignition On.
5. Measure Voltage.

9998699 pin# Expected value

11-13 U≈2.5V ±0.2V
14-13 U≈2.5V ±0.2V
15-13 U≈Vbat(+)
If Value not as Expected:
Measurement 1 Verify that the alternator reducer is connected according to the installation instructions.
Check all aux/multilink wiring, CAN terminations and connectors connected to the alternator
reducer. Check for open circuit, short circuit, bad connections.

AUX Connector
Aux pin# 9998699 pin# Signal
1 - -
2 11 CAN L
3 - -
4 13 Supply (-)
5 14 CAN H
6 15 +15 (ignition)
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Checking the alternator voltage reducer output

1. Main switch Off.
2. Connect 88890016 between alternator reducer connector and alternator connector.
3. Main switch On.
4. Start the engine.
5. Measure Voltage.

12V
Signal Expected value Note
Alt. B(+) - B(-) U≈14V ±0.3V Alternator output

9998699 pin# Expected value Note

bat(+) - 12 U≈2.5V ±0.3V -
U ≈ Vbat(+) - Vd (if measured at alternator pin1)
15-13 U≈Vbat(+)
(Vd=voltage drop over resistor)

24V
Signal Expected value Note
Alt. B(+) - B(-) U≈28V ±0.3V Alternator output

Measurement 2 9998699 pin# Expected value Note

10-13 U≈12V ±1V -
14-13 U≈Alt B(+) -
15-13 U≈Alt B(+) - Vd Vd=voltage drop over diod unit

If any measured value deviates from expected:

Verify that the alternator reducer is connected according to the installation instructions.
Check all wiring between the alternator reducer and the alternator. Check for open circuit, short
circuit, bad connections.
Check that alternator “sense” is connected to bat(+).

Voltage Reducer Connector

Output pin# 9998699 pin# Signal
1 10 24V PWM (only 24V), HS switch
2 - Not used
3 12 12V PWM (only 12V), LS switch
4 13 B(-)
5 14 D/L (only 24V)
6 15 12/24 activation/magnetisation, HS switch

12V: 24344455
Schematic
24V: 24343677

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CAN Bus, check

A HS CAN Bus (High Speed CAN Bus) has a speed of 125kbit/s - 1Mbit/s and needs to be terminated with 120 Ω in
each end. A CAN bus uses three wires for communication: CAN H, CAN L and GND.

Troubleshooting the CAN bus can be done using a multimeter. Multimeter measurements will provide a lot of informa-
tion that will be enough in most cases. To the get the best view of the CAN bus status an oscilloscope can be used.

Signal Logical 0 Logical 1 CAN H and CAN L each has two distinctive voltage levels
when transmitting data.
CAN H-GND 3.5V 2.5V
When no device sends any data, bus is idling, both CAN
CAN L-GND 1.5V 2.5V signals will be 2.5V.

Resistance Measurement
Special tools
Measuring box
Multimeter
Break-out cable

1. Main switch Off

2. Connect correct brake-out cable + break-out box.
3. Measure Resistance. Start with checking that the termination resistors are connected and not faulty.

For correct CAN pin information, use the wiring diagram/connector pin-out for the component/circuit of interest.

Signal Expected Value

CAN H-CAN L R≈60 Ω

If Value not as Expected

Measured
Signal Possible Root Cause Suitable Action
Value
Disconnect the CAN wiring circuit in the middle of the
backbone circuit to narrow down the fault tracing.
Measure the resistance from the disconnected middle
towards each terminated end to locate in which half of the
CAN H-CAN L R≈0 Ω Short Circuit
backbone the fault is present.

R≈120 Ω indicates that circuit is ok.

R≈0 Ω indicates Short Circuit.
3 termination resis-
CAN H-CAN L R≈40 Ω Check the number of termination resistors.
tors
Check the termination resistors.
Disconnect the CAN wiring circuit in the middle of the
backbone circuit to narrow down the fault tracing.
Measure the resistance from the disconnected middle
1 termination resis- towards each terminated end to locate in which half of the
CAN H-CAN L R≈120 Ω tor/faulty resistor. backbone the fault is present.
Open Circuit.
R≈120 Ω indicates that circuit is ok.
R≈kΩ indicates Open Circuit.
(If CAN devices are connected, R will show kΩ. If not con-
nected R will show MΩ/Open Line.)
Note: The resistance measurement does not check the stub wiring. If stub wiring is suspected, measure CAN H-GND
and CAN L-GND voltage in the CAN device connector with the CAN device disconnected.
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Voltage Measurement
Special tools
Measuring box
Multimeter
Break-out cable

1. Main switch Off.

2. Connect correct brake-out cable + breakout box.
3. Main switch On.
4. Ignition On.
5. Measure Voltage.

For correct CAN pin information, use the wiring diagram/connector pin-out for the component/circuit of interest.

Signal Expected Value Note

Voltage level depends on bus load. If bus is at idle, no messages,
CAN H-GND U≈2.7V
U=2.5V.
Voltage level depends on bus load. If bus is at idle, no messages,
CAN L-GND U≈2.3V
U=2.5V.
GND=Bat(-) in CAN connector.

If Value not as Expected

Measured
Possible root cause Suitable Action
Value
U=0V Bus sleeping Confirm Ignition On.
Disconnect both termination resistors to separate CAN H and CAN L.
U≈0V Short Circuit to GND Measure CAN H-GND and CAN L-GND. The wiring that has a short
circuit will still read a low voltage value.
Main switch Off/Power Off.
CAN H≈2.3V Disconnect the CAN wiring circuit in the middle of the backbone cir-
and cuit to narrow down the fault tracing.
CAN H Open Circuit
CAN L≈2.3V Measure the resistance from the disconnected middle towards each
terminated end to locate in which half of the backbone the fault is
present.
CAN L≈2.7V
and CAN L Open Circuit R≈120 Ω indicates that circuit is ok.
CAN H≈2.7V R≈kΩ indicates Open Circuit. (If CAN devices are connected,
R will show kΩ. If not connected R will show MΩ/Open Line.)
Main switch Off/Power Off.
Disconnect the CAN wiring circuit in the middle of the backbone cir-
cuit to narrow down the fault tracing.
CAN L≈2.5V Measure the resistance from the disconnected middle towards each
CAN H & CAN L
and terminated end to locate in which half of the backbone the fault is
Short Circuited
CAN H≈2.5V present.

R≈120 Ω indicates that circuit is ok.

R≈0 Ω indicates Short Circuit.
CAN L≈bat(+) Disconnect both termination resistors to separate CAN H and CAN L.
CAN H/CAN L
and Measure CAN H-GND and CAN L-GND. The wiring that has a short
Short Circuit to bat(+)
CAN H≈bat(+) circuit to bat(+) will still read bat(+).

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EMS, check

Description
To fault trace an engine control unit (EMS) the following measurement table shall be used. All measured results must
be written into the table and the document must accompany a warranty claim.

The measurements are made to discover whether the fault is in the ECU, the wiring harness or in a component. All
measurements must be done before the ECU is removed.

Special tools
9990014 Brake-out cable
9998699 Measuring box
88890074 Multimeter

The grey connector is the B connector.

The black connector is the A connector.

1. Connect brake-out cable 9990014 to brake-out box

9998699.
2. Connect one of the engine control unit connectors to
brake-out cable 9990014.
3. Connect the brake-out cable 9990014 to the engine
control unit.
4. Use the measuring box to access all pins of the en-
gine control unit.

Chassis ground, check

Expected Measured
Measuring points
Value Value
Bat(+)-Bat(-) U=VBat

Bat(+)-chassis ground U=VBat

Be sure to check that a proper chassis ground/Bat(-)

measuring point is chosen. Check this by measuring be-
tween Bat(+) and the chosen chassis ground point.

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Connector A and B, ground check

1. Main switch Off.

2. Connect correct brake-out cable + breakout box.
3. Measure Resistance.

Expected Value
Component EMS Pin 9998699 Pin# Measured Value
(Main power Off)

A57-chassis ground 57-chassis ground

B58-chassis ground 58-chassis ground

EMS ground
B59-chassis ground 59-chassis ground

B61-chassis ground 61-chassis ground

A6-chassis ground 6-chassis ground

A11-chassis ground 11-chassis ground

R≈0-2 ohm
A15-chassis ground 15-chassis ground

A42-chassis ground 42-chassis ground

Sensor ground
A62-chassis ground 62-chassis ground

B6-chassis ground 6-chassis ground

B10-chassis ground 10-chassis ground

B18-chassis ground 18-chassis ground

Connector A and B, supply check

1. Engine Off.
2. Ignition On.
3. Measure Voltage.

Expected Value
Component EMS Pin 9998699 Pin# Measured Value
(Ignition On)

A7-A11 7-11
5V Supply U≈4.75V-5.25V
B17-B18 17-18

B57-B58 57-58
Power Supply EMS U≈Vbat
B60-B58 60-58

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Connector A, signal check

1. Engine Off.
2. Ignition On. All sensors are not available on all engine variants so
3. Measure Voltage. the expected value could differ if sensor is missing.

9998699 Expected Value Measured

Component EMS Pin Notes
Pin# (Ignition On) Value

Fan speed sensor

A1-A57 1-57 U≈Vbat
supply

Coolant pump A4-A57 4-57 U≈Vbat

At T=20 °C (68 °F) (Higher

Rail temperature A5-A57 5-57 U≈3.1V ±0.2V
T=Lower measured voltage)
Fuel quantity regu-
A16-A57 16-57 U≈Vbat
lator
Voltage depended of engine
Rail pressure A19-A57 19-57 U≈0.5V-0.9V
type.

Diff. pressure EGR A21-A57 21-57 U≈0.5V

Air inlet pressure A22-A57 22-57 U≈1.0V ±0.2V At sea level.

U≈Vbat Engine stop switch inactive.

Engine stop switch A27-57 27-57
U≈0V Engine stop switch active.

ePRV A28-A57 28-57 U≈Vbat

With clean filter (no activated

Air filter indicator A29-A15 29-15 U≈2.9V ±0.4V
switch)
At T=20 °C (68 °F) (Higher
Oil temperature A31-A57 31-57 U≈3.1V ±0.2V
T=Lower measured voltage)
Crankshaft speed, No signal when Coil resistance: 0.9kOhm ±10%
A38-A37 38-37
inductive engine off At T=20 °C (68 °F)
No signal when
Fan speed A39-A35 39-35
engine off

Turbo speed A41-A57 41-57 U≈5V ±0.2V

Camshaft speed, No signal when Coil resistance: 0.9kOhm ±10%

A46-A45 46-45
inductive engine off At T=20 °C (68 °F)
Intake manifold At T=20 °C (68 °F) (Higher
A47-A57 47-57 U≈3.4V ±0.2V
temperature T=Lower measured voltage)

Seawater pressure A50-A57 50-57 U≈0.5V

Coolant pressure A54-A57 54-57 U≈0.5V

Ignition On A58-A57 58-57 U≈Vbat

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Connector B, signal check

1. Engine Off.
2. Ignition On. All sensors are not available on all engine variants so
3. Measure Voltage. the expected value could differ if sensor is missing.

9998699 Expected Value Measured

Component EMS Pin Notes
Pin# (Ignition On) Value

Throttle motor supply B1-B5 1-5 U≈Vbat

U=≈.8 x Vbat Relay activated

Preheat sense B7-B58 7-58
U≈0V Relay not activated

Water in fuel B8-B58 8-58 U≈4.8V ±0.2V When no water in fuel

EGR valve B9-B58 9-58 U≈Vbat

Oil pressure B11-B58 11-58 U≈0.5V

Exhaust pressure B12-B58 12-58 U≈0.5V

Fuel pressure B16-B58 16-58 U≈0.5V

Oil piston cooling jet

B19-B58 19-58 U≈0.5V
pressure

Fuel pressure leakage B20-B58 20-58 U≈0.5V

Backbone2 CAN L B21-B58 21-58 U≈2.3V ±0.3V

Backbone2 CAN H B22-B58 22-58 U≈2.7V ±0.3V

Coolant level B23-B58 23-58 U≈0.8 x Vbat

Throttle position B24-B58 24-58 U≈0.5V-4.4V Depended of throttle position

U≈Vbat Relay not activated

Preheat relay B25-B58 25-58
U≈0V Relay activated

At T=20 °C (68 °F) (Higher

Coolant temperature B27-B58 27-58 U≈3.4V ±0.2V
T=Lower measured voltage)

VCB valve B30-B58 30-58 U≈Vbat

At T=20 °C (68 °F) (Higher

Air filter temperature B31-B58 31-58 U≈2.5V ±0.5V
T=Lower measured voltage)
At T=20 °C (68 °F) (Higher
Fuel temperature B32-B58 32-58 U≈3.4V ±0.2V
T=Lower measured voltage)

Engine subnet CAN L B35-B58 35-58 U≈2.3V ±0.3V

Engine subnet CAN H B36-B58 36-58 U≈2.7V ±0.3V

Wastegate valve B38-B58 38-58 U≈Vbat

Oil piston cooling jet

B41-B58 41-58 U≈Vbat
valve

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Exhaust temperature,
B43-B58 43-58 U≈0.2V-0.8V Depended of temperature
wet
Exhaust temperature,
B44-B58 44-58 U≈0.2V-0.8V Depended of temperature
dry

EGR temperature B48-B58 48-58 U≈0.7V-2.2V Depended of temperature

Fan clutch B49-B58 49-58 U≈Vbat

Backbone1 CAN H B51-B58 51-58 U≈2.7V ±0.3V

Powertrain CAN H B52-B58 52-58 U≈2.7V ±0.3V

Oil thermostat valve B53-B58 53-58 U≈Vbat

Backbone1 CAN L B55-B58 55-58 U≈2.3V ±0.3V

Powertrain CAN L B56-B58 56-58 U≈2.3V ±0.3V

B57-B58 57-58
Main relay activated U≈Vbat
B60-B58 60-58

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HCU, check (EVC2)

VODIA test routines
To check LEDs, buttons and the lever/levers on a HCU
there are three different test routines:

• Helm Station LED Test

• Helm Station Button Test
• Helm Station Control Lever Test

All three tests shall be used when conducting fault trac-

ing on a HCU. All test routines results are stored in “User
Sessions”.

Helm Station LED Test

The HCU LED test will light up all LEDs on all HCUs.
Visually inspect that all LEDs are lit. After all LEDs are
visually checked, stop the test.

Helm Station Button Test

The HCU button test will check that the HCU can detect
when a button is pressed. All buttons on a HCU can be
checked.

All buttons listed in the test will not be available for every
HCU. Skip if not available.

Helm Station Control Lever Test

The HCU lever test will check that the HCU can detect all
lever positions.

Forward, neutral and neutral lever position is checked.

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HCU Connectors
• EVC Bus (x2)
• Multilink Bus (x5)
• Steering Control Bus (x8)
• Key Switch/Start Stop Panel (x4)

Special tools:
88890016 Brake-out cable (x2, x5)
88890161 Brake-out cable (x4, x8)
9998699 Measuring box

Resistance Measurement
1. Main switch Off.
2. Connect correct brake-out cable + measuring box.
3. Measure Resistance. Start with checking that the termination resistors are connected and not faulty.

EVC Bus (x2), (use 88890016)

9998699 Measuring
Signal Pin (x2) Expected Value (Ignition On) Measured Value
Pin# Points
CAN L x2:2 11
11-14 R≈60 Ohm
CAN H x2:5 14
Note: EVC2 requires a termination cable (white) connected to X2.

Voltage Measurement
1. Main switch Off.
2. Connect correct brake-out cable + measuring box.
3. Main switch On.
4. Ignition On.
5. Measure Voltage.

EVC Bus (x2), (use 88890016)

9998699 Measuring
Signal Pin (x2) Expected Value (Ignition On) Measured Value
Pin# points
Supply Voltage (E+) x2:1 10 10-12 U≈VBat(+)
CAN L x2:2 11 11-12 U≈2.5V ±0.2V
Supply Voltage (E-) x2:3 12 - -
Supply Voltage (C-) x2:4 13 - -
CAN H x2:5 14 14-12 U≈3.0V ±0.2V
Supply Voltage (C+) x2:6 15 15-13 U≈VBat(+)

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Multilink Bus (x5), (use 88890016)

9998699 Measuring
Signal Pin (x5) Expected Value (Ignition On) Measured Value
Pin# points
CAN L (in) x5:1 10 10-13 U≈2.4V ±0.2V
CAN L (out) x5:2 11 11-13 Uv2.4V ±0.2V
CAN H (in) x5:3 12 12-13 Uv2.6V ±0.2V
Supply Voltage (-) x5:4 13 - -
CAN H (out) x5:5 14 14-13 U≈2.6V ±0.2V
Supply Voltage (+) x5:6 15 15-13 U≈VBat(+)

Steering Control Bus (x8), (use 88890161)

9998699 Measuring
Signal Pin (x8) Expected Value (Ignition On) Measured Value
Pin# points
Supply Voltage (+) x8:1 5 5-7 U≈VBat(+)
CAN L x8:2 6 6-7 U≈4.2V ±0.2V
Supply Voltage (-) x8:3 7 - -
Supply Voltage (+) x8:4 8 8-7 U≈VBat(+)
CAN H x8:5 9 9-7 U≈0.8V ±0.2V
Supply Voltage (-) x8:6 10 - -

Key Switch/Start Stop (x4), (use 88890161)

9998699 Measuring
Signal Pin (x4) Expected Value (Ignition On) Measured Value
Pin# points
CAN L x4:1 11 11-16 U≈2.4V ±0.2V
CAN H x4:2 12 12-16 U≈2.6V ±0.2V
Key Panel Supply
x4:3 13 - -
Voltage (-)
Key Panel Supply
x4:4 14 14-13 U≈VBat(+)
Voltage (+)
Supply Voltage (+) x4:5 15 15-16 U≈VBat(+)
Supply Voltage (-) x4:6 16 - -
Not used x4:7 17 - -
LIN Communication x4:8 18 18-16 U≈20V ±2V

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PCU, check
Special tools:
9998699 Measuring box
88890074 Multimeter
88890173 Break-out cable

Voltage Measurement
1. Main switch Off.
2. Connect correct brake-out cable + measuring box.
3. Main switch On.
4. Ignition On.
5. Measure Voltage.

Use a wiring diagram for the installation type that is checked, to identify which in/outputs that are used.

Note: Since the PCU has a 70-pin connector some measurements require 2 measuring boxes.

Measuring 9998699 Expected Value

Signal Notes
points Pin# (Ignition On)

Gearshift solenoid/actuator
1-25 1-25 U≈Vbat FWD Gear Engaged
control, primary

Ignition signal, Key switch 3-20 3-20 U≈Vbat Ignition On

EVC bus CAN L 6-69 6-(7*) U≈2.5V ±0.2V *Measuring box#2

Control signal for Power Trim,

7-20 7-20 U≈Vbat
UP (Aq)
Solenoid activated.
Trolling solenoid control (ZF) 7-9 7-9 U≈Vbat see wiring diagram for Troll-
ing solenoid connection
U≈Vbat (CWES Close)
7• -11• 7-11
CWES motor control (IPS) U≈-Vbat (CWES Open) see wiring diagram for CWES
U≈Vbat (CWES Open) connection
8• -9• 8-9
U≈-Vbat (CWES Close)
Control signal for Power Trim,
Down (Aq) 8-20 8-20 U≈Vbat

If power trim position sensor

U≈4.5V ±0.3V connected (Aq, DPI)
5V Supply 12-20 12-20 If U>5V no sensor connected.
If RPM sensor connected
U≈5V
(IPS)
Potentiometer is connected.
Powertrim potentiometer
12-13 12-13 U≈3.5V U>5V no potentiometer is
supply
connected.

Auxiliary bus CAN H 14-40 14-40 U≈2.5V ±0.2V

5V Supply 15-45 15-45 U≈5V ±0.2V

21-20 21-20
Power Supply PCU U≈Vbat
22-23 22-23

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Gearshift solenoid/actuator
24-48 24-48 U≈Vbat Reverse Gear Engaged
control, secondary

Backbone2 CAN H 26-20 26-20 U≈2.7V ±0.3V

EVC bus CAN H 30-69 30-(7*) U≈3.0V ±0.2V *Measuring box#2

If sensor connected.
5V supply 35-20 35-20 U≈5V ±0.2V
U>5V=no sensor connected.

Feedback, Power Trim signal 36-13 36-13 U≈0.2-0.9V Depends of trim angle

Auxiliary bus CAN L 38-40 38-40 U≈2.5V ±0.2V

Backbone1 CAN H 44-20 44-20 U≈2.7V ±0.3V

Datalink supply (E) 46-69 46-(7*) U≈Vbat *Measuring box#2

Datalink supply (C) 47-70 47-(8*) U≈Vbat *Measuring box#2

Backbone2 CAN L 51-20 51-20 U≈2.3V ±0.3V

U≈Vbat (CWES Open)

CWES Position Signal 53-13 53-13
U≈-Vbat (CWES Close)

5V supply 54-45 54-45 U≈5V ±0.2V

Oil quality feedback 58-45 58-45 U≈0.5V-4.5V

0.5V at Ignition On if sensor

Oil pressure 59-45 59-45 U≈0.5V-4.5V
connected.

U≈0.9V x VBat No sensor connected

Fuel level 62-39 62-39
U≈0-3.7V Depended of fuel level

Switched AUX+ 63-20 (1*)-20 U≈VBat *Measuring box#2

0.5V at Ignition On if sensor

connected.
Oil pressure 64-45 (2*)-45 U≈0.5V-4.5V
U>5V=no sensor connected.
*Measuring box#2
Depended of temperature if
sensor connected.
Oil temperature 66-45 (4*)-45 U≈0.5V-4.5V
U>5V=no sensor connected.
*Measuring box#2

Backbone1 CAN L 68-20 (6*)-20 U≈2.3V ±0.3V *Measuring box#2

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44 - Transmission

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Steering Function DPI, check

Description
To check the steering function of the DPI drive there are
different actions that needs to be performed. To do a
complete function control of the system the “Steering
control flow chart” shall be used.

Perform all steps thoroughly before deciding if there is a

need of conducting troubleshooting on the actual drive.
This to avoid an unnecessary boat lift.

This graphical illustration shows how the steering system

is set up. To perform a complete troubleshooting all parts
shown in the illustration needs to be checked.

A steering angle request from the steering wheel is transferred via the steering control
Steering wheel -> HCU
bus to the HCU.

HCU -> SCM From the HCU the steering angel request is transferred via the EVC bus to the SCM.

The SCM controls the steering motor in the electro-hydraulic system that turns the
SCM - > Steering Motor
drive. (for hydraulic schematic see Design & Functions, Marine transmissions)

A drive angle feedback is sent to the SCM.

Drive Position sensor1 ->
The drive position sensor is a touch less axial absolute/rotary encoder/magnet and
SCM
decoder sensor that contains of two sensors, A and B, for redundancy.

1 “Drive Position Sensor = Rudder Angle Sensor = Drive Position Angle Sensor”

Perform a visual inspection

(especially important if components been dismounted during a repair or exchanged.)

• Check that there is no hydraulic leakage within the hydraulic system. Leakage in the system could affect the steer-
ing performance.
• Check that all hoses are correctly connected. If wrongly connected the drive will turn to end position during self
test.
• Check that all wiring are correctly connected. If the drive position sensor been changed, check that the sensor is
correctly pinned in the connector.
• Check the battery condition. A poor battery status could affect the steering performance.

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Checking DPI steering function

Always start by creating a VODIA template and log, if
possible, on a fault free driveline. Compare the result with
the fault setting driveline.

Create a VODIA template with following parameters:

P1UVD - Control Module Voltage
P1TXV - a
Create EVC,
logSteering Actuator, Supplementary Power Supply Voltage
template
P1TX8 - EVC, Steering Actuator, Drive Position, Angle Sensor A, Indicated Angle
P1TYB - EVC,start
If possible Steering
theActuator, Drive Position,by
troubleshooting Angle Sensordata
collect B, Indicated
from Angle
a fault free driveline. This data can be used for comparison.
P1TX2 - EVC, Steering Motor, Momentary Torque
P1C69 - ECU Temperature
1. Start the VODIA log.
2. Start the engine.
When starting the engine a drive self test is initiated.
The drive will start to move to reach center position
Start and thereafter wiggle the drive a few degrees from
side to side.
3. Steer the drive from side to side at different speeds
to collect data.

Perform a visual inspection of:

- All wiring and connectors from the SCM.
- All hydraulic hoses and connections.

Start a VODIA log using the SCM log template.

Start the engine. After the drive has performed its

selftest steer the drive from side to side.

If the self test fails or if the drive is in failsafe safe mode

(because of a faulty steering sensor), try turning the drive
using the emergency steering option. This will make it
Analyze the VODIA log possible to check the status of steering sensor A and B.

Perform Measurements

End

Steering control troubleshooting flow chart.

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A VODIA log that shows that the drive self test is performed correctly and that drive position angle sensors A and B
follow each other as expected while the drive is turning from side to side. The execution of the self test is seen as a
small change of the drive position angle values early in the log.

The drive position sensor A and B parameter values will, when logged by VODIA, in fault free conditions follow
eachother and show the same angle values while the drive is turning. This because the sensor voltage outputs been
converted to an angle in the SCM.
Notice the self test plot at the start of the logging.

The drive position sensor A and B voltage outputs will not, when measured with a multimeter, in fault free condition
follow eachother. Instead one value will increase while the other one will decrease while turning the drive.
A oscilloscope log of the drive self test and a steering sequence end to end.
Notice the self test plot at the start of the logging.

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Analyzing the log

1. Check that the drive self test is performed. If performed correctly both drive position angle sensors A and B will
follow eachother and show the same angle values and the drive will be centered.
If the drive turns to an end position during the self test:
- Hoses are incorrectly connected.
- Steering motor is incorrectly connected.
- Steering sensor wiring is incorrectly pinned.
2. Check that both steering angle A and B parameter values follow eachother while the drive is turning.
If the sensors values show any irregularity:
- Check all wiring and connectors between the SCM and the drive position sensor.
3. Check that there are no dips or other inconsistency in any of the “Control Module Voltage” and “Supplemantary
Power Supply Voltage” parameter readings during the test run.
4. Check that there is no high transient peak in the momentary torque value that could indicate an obstruction in the
steering motor.

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Perform measurements
The final step in troubleshooting the steering function is to perform a couple of measurements. If a fault free driveline
is available a comparison between the drivelines can be made.

• Start checking the drive position angle sensor at the SCM.

If any fault is detected, check all connectors from the SCM to the sensor.
• If drive position angle sensor A or B show a out of range value when turning the drive, then turn the drive to end
position to check which sensor that is correct. Check for a voltage drop in the sensor wiring for the out of range
sensor.

Drive Position Angel Sensor, check

Description The drive position angel sensor is connected to the SCM.

Possible DTC C100002, C100162 C100177, P100008
9998699 Measuring box
Special tools 88890074 Multimeter
88890016 Break-out cable
Voltage measurement
1. Main switch Off.
2. Connect 88890016, 12-pin, Break-out cable between the SCM and the SCM connector.
3. Main switch On.
4. Ignition On.
5. Measure Voltage.

9998699 Pin# Expected value

27-32 U≈0.8-4.1 V (Port = increase, STBD = decrease)
28-31 U≈0.8-4.1 V (Port = decrease, STBD = increase)
29-31 U≈5V
Measurement 30-32 U≈5V

12-pin connector
Pin# 9998699 Pin# Signal
4 27 Rudder_1, angle sensor A
5 28 Rudder_2, angle sensor B
6 29 5V_OUT2
7 30 5V_OUT1
8 31 GND_OUT2
9 32 GND_OUT1

Normal drive angle: -22° to 22°

Technical data
(-24° to 24° when using emergency steering)
Wiring diagram 23073036
Incorrect connected drive position sensor or an unwanted voltage drop in the sensor wiring
Symptom
will turn the drive to end position.

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Steering Motor, check

Description The 3 phase steering motor is connected to the SCM.

P100396
Possible DTC
P100397
Special tools Multimeter
Resistance measurement
1. Main switch Off.
2. Disconnect the motor from the SCM and measure the cables going from the connector
to the servo steering motor.
3. Measure the resistance in the connector between 1-3(V-W), 1-2(V-U), 2-3(U-W). Check
that there is no “Open Circuit” or unwanted resistance. The resistance should be the
same between all measurements.
4. Reconnect the motor to the SCM.

Pin# Expected value

1-3 R≈0
1-2 R≈0
2-3 R≈0

Measuring Voltage
1. Main switch On.
2. Ignition On.
3. Start the engine.
4. Measure, at the motor connections, the voltage between V-W, V-U, U-W while turning the
drive. The voltage should be the same between all measurements.

Pin# Expected value

Measurement 1-3 U≈same as 1-2 and 2-3.
1-2 U≈same as 1-3 and 2-3.
2-3 U≈ same as 1-3 and 1-2.

Connector
Pin# Signal
1 BLDC_PH_B (V)
2 BLDC_PH_A (U)
3 BLDC_PH_C (W)
4 BLDC_GND (plugged)

If any wire to the steering motor is incorrectly connected the steering motor will turn the
Symptom
drive to end position.

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VODIA Log Parameters, DPI

P1TX8, Steering Actuator, Drive Position, Angle Sensor A, Indicated Angle

Description Indicates current steering angle of the drive, measured by the angle sensor A.
Normal value -22° (starboard) –> 22° (port)
Unit degrees
Fault indication -33,5° (e.g. faulty sensor, sensor not connected, etc.)

P1TYB, Steering Actuator, Drive Position, Angle Sensor B, Indicated Angle

Description Indicates current steering angle of the drive, measured by the angle sensor B.
Normal value -22° (starboard) –> 22° (port)
Unit degrees
Fault indication -33,5° (e.g. faulty sensor, sensor not connected, etc.)

P1TX2, EVC, Steering Motor, Momentary Torque

Shows the momentary torque of the steering motor. Based on a calculated value regarding
Description
current flow.
Normal value -
Unit Nm
Fault indication -327.68

P1TXV, EVC, Steering Actuator, Supplementary Power Supply Voltage

Description Shows the momentary supplementary power supply voltage measured by the SCM.
Normal value Vbat+
Unit voltage
Fault indication 65,535

P1UVD, Control Module Voltage

Description Power supply, SCM.
Normal value Vbat+
Unit voltage
Fault indication 65,535

P1C69, ECU Temperature

Description Internal ECU Temperature.
Normal value -
Unit Celcius
Fault indication -40°C; (e.g. faulty internal sensor)

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