19:01-18

Issue 2 en
program 99

Installation instructions - Industrial engines

Scania DEC2 control system, V7.0

Connection with snap-on connectors

Part No.
1 588 621 © Scania CV AB, Sweden, 2001-01:2
 Program 99

THE INSTALLING CONTRACTOR IS

RESPONSIBLE FOR AN OPERATIONAL
INSTALLATION IN ACCORDANCE WITH
SCANIA’S INSTALLATION INSTRUCTIONS.

THE CLASSIFICATION APPROVAL CAN

DEPEND ON MARKET SPECIFIC
CLASSIFICATION REQUIREMENTS.

Address enquiries to:

SCANIA CV AB
Industrial and Marine Engines
Service Support
S-151 87 Södertälje, Sweden
Tel. +46 8 553 810 00
Fax +46 8 553 831 80

Contents
Important . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Location of sensors on DC12 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Location of sensors on DI12 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Location of sensors on DI14 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Location of sensors on DI9 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Connection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
The DEC2 system without instrument panel . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
The DEC2 system with Scania instrument panel . . . . . . . . . . . . . . . . . . . . . . . . 9
The DEC2 system with the customer’s own instrument panel . . . . . . . . . . . . . 10
All speed engines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Single speed engines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Wiring diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Instructions for installation and dimension sketches . . . . . . . . . . . . . . . . . . . . . . . 18
Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

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 Program 99

Important
• Changes must not be made to the DEC2 control unit or sensors and wiring. Doing so may
effect the control unit’s safety system and cause damage to the operator, the engine or
driven equipment.
• Never splice a damaged cable. Change the entire cable, otherwise the safety and operation
of the system could be impaired.
• The sensors for the DEC2 control system are dedicated for use in DEC2 only.

In order to avoid damage to the DEC2 control unit the following items must be
considered:
• Check that the cables for the battery and alternator/s are properly connected before
starting the engine.
• Before disconnecting the cable to the control unit, all power to the unit should first be
switched off.
• Disconnect the DEC2 control unit when boost charging the battery.
• Disconnect the battery if arc welding.

General
This booklet describes how the DEC2 sys- Sensors
tem is connected to the Scania main supply
box DEC2 containing fuses, relays and All sensors required for the DEC2 control
switches. system are fitted or connected to the engine
Also the accelerator position sensor and the at delivery. The locations of the sensors are
power supply are connected to the main shown on pages 4, 5, 6 and 7.
supply box. The connection to the box is
done by the supplied connectors. Junction box
The junction box can also be connected,
using the supplied connectors, to the other The junction box is fitted on the engine at
Scania electrical systems and instrument delivery. The location of the junction box is
panel. shown on pages 4, 5, 6 and 7.
See booklet 19:01-17, Electrical system, for
more detailed information. Cable harness
The cable harness for connection to the con-
trol unit has a length of 6 m (standard
length) and is connected to the junction box
at delivery.

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 Program 99

Location of sensors on DC12

1. Boost pressure
2. Boost temperature
3. Oil pressure
4. Junction box
5. Coolant temperature
6. Engine speed

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 Program 99

Location of sensors on DI12

1. Boost pressure
2. Boost temperature
3. Oil pressure
4. Junction box
5. Coolant temperature
6. Engine speed

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 Program 99

Location of sensors on DI14

(location of sensors is similar on DC14)

1. Boost pressure
2. Boost temperature
3. Oil pressure
4. Junction box
5. Coolant temperature
6. Engine speed

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 Program 99

Location of sensors on DI9

(location of sensors is similar on DC9)

1. Boost pressure
2. Boost temperature
3. Oil pressure
4. Junction box
5. Coolant temperature
6. Engine speed

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 Program 99

Connection

The DEC2 system without

instrument panel
The DEC2 system can be connected without using
the Scania instrument panel as follows:
- Connect the main supply box 2 for DEC2 to the
control unit 1 using connectors C36 and C90.
- Connect the other part of connector C76. When
doing so some pins are jumped when Scania
instrument panel is not used.
- Connect battery power supply, 24V, to connec-
tor C75, red cable to plus (+) and black cable to
minus (-).
- Connect the accelerator position sensor 3 to
connectors C189 and C190. For all speed engi-
nes, see page 11 and for single speed engines,
see page 12.

1. DEC2 control unit

2. Main supply box for DEC2
3. Accelerator position sensor (APS) for all speed engines
4. Connection to the rest of the electrical system

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 Program 99

The DEC2 system with Scania

instrument panel
The DEC2 system and Scania instrument panel
are designed to make the connection into a well
functioning system easy.
- Connect the main supply box 2 for DEC2 to
the control unit 1 using connectors C36 and
C90.
- Connect the connectors C75 and C76 inside the
engine junction box 4.
- Connect the instrument panel 6 to the junction
box 4 with the connection cable 5.
- Connect the accelerator position sensor 3 to
connectors C189 and C190. For all speed engi-
nes, see page 11 and for single speed engines,
see page 12.

1. DEC2 control unit

2. Main supply box for DEC2
3. ccelerator position sensor (APS) for all speed engines
4. Junction box for engine and instrument panel
5. Connection cable (extension cable)
6. Instrument panel

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 Program 99

The DEC2 system with the - Connect the accelerator position sensor 3 to
customer’s own instrument panel connectors C189 and C190. For all speed engi-
nes, see page 11 and for single speed engines,
- Connect battery power to connector C75. see page 12.

- Connect a key switch, stop switch and the war-

ning lamp (main indicator lamp) for the DEC2
system to connector C76.

1. DEC2 control unit

2. Main supply box for DEC2
3. Accelerator position sensor (APS) for all speed engines
4. Connection to the rest of the electrical system and to the instrument panel
5. Battery
6. Key switch
7. Stop switch
8. Warning lamp (main indicator lamp) for DEC2

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 Program 99

All speed engines

With Scania accelerator position sensor

(APS)
Connect the accelerator position sensor with con-
nectors C189 and C190. The third connector,
C191 is only used as kick-down switch together
with an automatic gear box.
1. Accelerator position sensor
2. Main supply box for DEC2

With other accelerator position sensor

Open the main supply box for DEC2 and connect
connector C77 to plus (+) on a free pin on termi-
nal C73 in order to simulate the idle switch which
in most cases is not included in other accelerator
position sensors.

Main supply box for DEC2

Connect the accelerator position sensor to connec-

tor C190. Connector C189 is only used as kick-
down switch together with an automatic gear box.

1. Accelerator position sensor

2. Main supply box for DEC2

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 Program 99

Single speed engines

Connect a trim potentiometer for fine adjustment
of the speed to connector C190.

1. Potentiometer
2. Main supply box for DEC2

Running with fixed speed

Open the main supply box for DEC2 and connect
connector C77 to plus (+) on a free pin on termi-
nal C73.
Connector C189 is not used at fixed speed.

Main supply box for DEC2

Running with idle / fixed speed

Connect a switch to C189 for changing between
idle speed and running speed. The switch should
switch between minus (-) for idle speed and plus
(+) for running speed.

1. Switch for idle speed/running speed

2. Main supply box for DEC2

Running with isochronous speed

Connect the violet cable marked D/I to plus (+) on
a free pin at terminal C73 in the main supply box.

Running with droop

Connect the violet cable marked D/I to minus
(-) on a free pin at C87 in the main supply box.

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 Program 99

Different applications for single speed

engines
1. No adjustment of the speed (fixed speed)
Connect connector C77 to plus (+) on a free pin
on terminal C73.
Green cable marked SH should be connected to
plus (+) at C73 in order to put the trim pot input
out of function
Note that no trim potentiometer should be con-
nected.
Connect the engine for isochronous operation as Main supply box for DEC2
shown on page 12.

2. Manual adjustment of the speed

Connect connector C77 to plus (+) on a free pin
on terminal C73.
Green cable marked SH should be connected to
minus (-) on a free pin at C87 in order to make
adjustment of the speed with a trim pot possible.
The range of adjustment is ±90 rpm (±3 Hz).
Connect the engine for operation with droop as
shown on page 12.
Main supply box for DEC2

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 Program 99

3. Remote controlled speed adjustment

- Connect connector C77 to plus (+) on a free
pin on terminal C73.
- Connect an external speed adjustment not deli-
vered by Scania to connector C190, pins B and
C. The signal voltage should be between 0 to 5
V in order to be able to adjust the speed
+/- 90 rpm (+/- 3 Hz).

4. Load sharing and synchronizing equipment Huegli Tech AG

Equipment for load sharing and synchronizing can Att: Product Manager
be connected to the DEC2 control unit. This
equipment will not be delivered by Scania but Tel. 41 (0)62 916 50 30
directly from our GAC equipment supplier in Fax. 41 (0)62 916 50 35
Europe
E-mail. hueglitechag@bluewin.ch
Customers who wish to procure such equipment
should therefore contact Huegli directly. They
will produce a recommendation for every specific
application and supply the necessary equipment.

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 Program 99

Wiring diagrams

Component list for wiring diagram

Com-
Denomination Description
ponent
B25 Switch Idle, safety switch
B26 Switch Kick-down (only used together with an automatic
gear box)
C36 Connector 12 pole
C67 Junction Reference point
C73 Junction 4 pole, +24 V
C75 Connector 2 pole
C76 Connector 7 pole
C77 Connector 1 pole
C78 Junction
C79 Junction
C87 Junction 8 pole, connection to minus
C90 Connector 8 pole
C91 Connector 7 pole
C92 Connector 2 pole
C189 Connector 2 pole
C190 Connector 3 pole
C191 Connector 3 pole
D8 Potentiometer Single speed engine
D14 Diode
D35 Potentiometer All speed engine
F7 Fuse 16 A, battery+24 V
F8 Fuse 16 A, battery minus
F9 Fuse 5 A, battery +24 V
F10 Fuse 5 A, battery minus
R20 Relay Supply 16 A
R22 Micro relay Supply 5 A
R23 Micro relay Warning lamp
S18 Switch Stop
S20 Switch Lamp test / Fault code test
S30 Rotary switch On / Off, supply voltage
W15 Indicator lamp Diagnos, engine room

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 Program 99

Colour codes for electric cables

Code Colour
bk black
bn brown
rd red
og orange
ye yellow
gn green
bu blue
vt violet
gy grey
wh white
pk pink

Example of cable designation

15D.bn-1.5
denotes the following:
15D cable marking
bn cable colour
1.5 cable area. If not otherwise stated the cable area is 0,75 mm2.

Main supply box for DEC2

A Connected to DEC2 by C36 and C90
B Connected in accordance with one of the two following alternatives:
- C75 and C76 to the main supply box for Scania electrical system with instrument panel
- C75 to battery power supply and C76 for jumping the signals to DEC2 when not using Scania
instrument panel
C Insulated and not used
D Insulated and not used. Connected to C91 when load indication signal is used.
E Connection to Scania accelerator position sensor.
F A trim potentiometer kan be used at single speed operation.
G Connections to C75 and C76 when not using Scania instrument panel.

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 Program 99

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 Program 99

Instructions for installation and dimension sketches

DEC2 control unit Avoid ground connection of the control

unit
Placing The control unit casing in the control unit with
- The control unit should be mounted separately program version 7.0 is directly connected to
from the engine but not farther away than the minus (-) on the printed circuit card. This condi-
supplied cable harness allows. tion means that the casing is directly connected to
battery minus (-).
- It should be mounted in an upright position as This has been done in order to further improve the
shown in the figure in order to prevent conden- protection of the control unit against electrical
sation water in the boost pressure hose and interference.
allow for drainage of any condensation water
in the housing. In order to avoid ground faults the control unit
casing must be fitted with the casing galvanically
- The LED display should be easy to read when isolated from e. g. the hull of a vessel
running the engine and when performing fault
This is very important to observe also when
diagnosis.
replacing a control unit having program V6.0
- The COMM/DIAG PORT should be easily due to the fact that only V7.0 control units are
accessible for connection. delivered as spare part.

Obs! The COMM/DIAG PORT may only be Boost pressure hose

used by authorized personnel.
We recommend that the boost pressure line is
- The control unit must be placed in such a posi- installed with an inclination and with the jointing
tion that it is easy to get access to the multi-pin sleeve at the lowest point. Open the jointing
connector, the connection of the boost pressure sleeve at frequent intervals, preferably with the
line, the adjustment screw and the measuring engine running at low load, in order to drain off
pin used at calibration of the control unit. any condensation water.
- The control unit must not be installed in the
vicinity of very strong electrical fields. Note When removing or replacing the
control unit, disconnect the hose for
the boost pressure at the jointing
Note When changing the control unit or
sleeve. Never disconnect the short
the injection pump, the control unit
hose from the control unit as there
must be calibrated, See Tuning and
is a great risk of damaging the inlet
calibration, 03:03-03 (V7.0)
nipple.

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 Program 99

1. Bracket for isolation of the control unit

2. Adjustment pot at calibration
3. Multi-pin connector
4. Communication / Diagnos port
5. LED-display
6. Measuring point at calibration
7. Jointing sleeve
8. Hose for boost pressure from the engine

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 Program 99

Main supply box DEC2

Fit the main supply box for DEC2 with TOP on the cover upwards and with
the drainage hole in the housing downwards.

1. Drainage hole
Shown from behind
1

Accelerator position sensor (APS)

1. Electrical/mechanical max position 5. Electrical/mechanical min position

2. Kick-down switch, on position 6. Not used
3. Full load 7. 4 pcs M6 screw, min length 12 mm
4. Safety switch, on position

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 Program 99

Cable lengths

1. 2 metre 6. 2 or 8 metre
2. 6 metre
3. 4 metre Note Maximum allowed length for cable 5
4. 2,5 metre is 24 m.
5. 2, 8 or 12 metre

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 Program 99

Specifications

Control unit
Power supply: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Nominal 24 V DC
The control unit is transient and reverse
voltage protected by a series diode.
Operating voltage. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . The DEC2 is designed to operate from a
battery voltage of (at least) 15 to 32 V DC.
Power consumption: . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 A maximum plus actuator driver
8 A continuous (20 A peak)
Polarity. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Negative ground, the casing must be isolated in
a 2 pole system
Ambient temperature range . . . . . . . . . . . . . . . . . . . . . . -40°C to +65°C
Relative humidity. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Up to 95%
Surface finish . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Fungus proof and corrosion resistant

Actuator solenoid
Resistance (Ω) at 20 °C . . . . . . . . . . . . . . . . . . . . . . . . . 0.5-0.8 Ω, Injection pump with ELAB
0.6−1.2 Ω, Injection pump with EHAB
0.6−1.2 Ω, Injection pump with
mechanical stop lever
Measure between C39 1 and 2

Control rack sensor

Resistance (Ω) at 20 °C . . . . . . . . . . . . . . . . . . . . . . . . . 17 - 23 Ω, Measure between:
C38- A and B, C38 A and C

Temperature sensors
Resistance (Ω) at °C for complete sensor . . . . . . . . . . . 37 334 ± 5 041 Ω -40°C
13 329 ± 1 491 Ω -20°C
5 382 ± 355 Ω 0°C
2 410 ± 195 Ω 20°C
621 ± 58 Ω 60°C
207 ± 23 Ω 100°C
129 ± 16 Ω 120°C
69 ± 11 Ω 150°C

Engine speed sensor

Resistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 486-594 Ω
Inductance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 187-253 mH, Measure between C41- 1 and 2
Distance between sensor and flywheel/gear ring. . . . . . 0,5 - 1,5 mm

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 Program 99

Fuel shut off valve

Resistance (Ω) at 20°C . . . . . . . . . . . . . . . . . . . . . . . . . . ELAB: 1 pole, 42 - 48 Ω
Measure between C155- 1 and ground
EHAB: 2 pole, 35 - 50 Ω
Measure between C155- 1 and 2

Oil pressure monitor

Opening pressure at increasing pressure . . . . . . . . . . . . 1,1 ± 0,15 bar
Closing pressure at decreasing pressure. . . . . . . . . . . . . 0,7 ± 0,15 bar

Power consumption for the discrete inputs/outputs

Power consumption: . . . . . . . . . . . . . . . . . . . . . . . . . . . . mindre än 100 mA
Applies for the following discrete inputs:
Droop/Isochronous (S16)
Power Control (MAP1/MAP2)(S17)
Run/Stop (S18)
Speed Hold /NoSpeed Hold (S19)
Idle safety switch (B25
Idle/Run switch (S24)
Lamp test/Fault code (S20)

C90-3 and C90-4 (reserved) should not consume any current but should be connected to battery -.

Power consumption for the throttle input interface

Power consumption: Accelerator position sensor
or trim potentiometer input . . . . . . . . . . . . . . . . . . . . . . less than 20 mA

Speed trim input (single speed)

• 5 kohm potentiometer
• 0,5 - 4,0 VDC operational (0 - 5 VDC maximum)

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