Dacia Pick-Up 1304/1305/1307. Service manual — part 38

IGNITION AND INJECTION

17

17 - 16

ELECTRONIC CONTROL UNIT

The electronic control unit is situated in the engine compartment and fixed on the right

bumper column. It is connected to the injection control cables through a 35 pins connector.

The information track between the control unit and the system components is as follows:

Fuel electric pump

Carbon canister purging

valve

Air T

EngineT

Battery U

Oxygen

sensor (

λ

λ

λ

λ )

ELECTRONIC

CONTROL UNIT

Oxygen heating sensor

Induction coil

Injector

Valve potentiometer (

α

α

α

α)

Idle motion regulator

Idle switch

Rotation

sensor ( n )

DESCRIPTION OF THE SYSTEM

17

IGNITION AND INJECTION

17 - 17

WARNING!

In case of electric welding on the vehicle, the battery the alternator and the electronic

control unit should be disconnected. In case of fine painting above 85°C, the electronic
control unit should be taken off the vehicle. When remounting the fixing screws of the
control unit should be well secured, in order to ensure a perfect electric contact to the
vehicle chassis.

The cabling connector to the computer won’t be disconnected or reconnected before

interrupting the contact to the engine and disconnecting the battery terminal (-).

The electric correspondence between the 35 pins of the electronic control unit and the

system elements should be according to the Table 1 (page 17-29) and to the afferent
electric diagram.

Taking into consideration the special construction of the connectors used for this cabling

system, their disconnection should be done (only after interrupting the contact to the
engine) by pushing the fuse and then by disconnecting it.

The connection should be done carefully; the fuse should assure a perfect fixing and

electric contact of the cable connectors to the system components.

Disconnection mode (according to the instructions):

- electronic control unit: pull the lock (1) arrow sense, hinge the connector and

disconnect (see drawing a);

- rods, induction coil: push the lock (2), then disconnect the connector (see drawing b);
- oxygen sensor: pull the locking valve, then disconnect the connector; front cables

connection: turn the coupling cassette (see drawing c).

Fig. c

Fig. b

Fig. a

DESCRIPTION OF THE SYSTEM

IGNITION AND INJECTION

17

17 - 18

The pin 23 should be tightly fixed to the mass.
The pin 16 is very important; it ensures a permanent supply (+) to the computer in order

to keep in its memory all the damages which might occur during the running and to introduce
the necessary connection at starting up for the ignition and injection system.
The system takes into consideration the wearing in time of the engine, introducing the
necessary correction factors for engine functioning under optimal parameters. When
reconnecting the battery, the computer rememorizes all the data sent by the sensors and the
possible damages of the system, after about 20 minutes of engine running.

The pins 33 and 18 are very important; they ensure the link between the computer

mass and the vehicle body.

DESCRIPTION OF THE SYSTEM

17

IGNITION AND INJECTION

17 - 19

Pin no. Injection and ignition system component MA 1.7 Wire position in the

computer

component connector

1

Control ignition coil ( cylinders 1 and 4 )

3

2

Not connected

-

3

Signal rotation sensor

2

4

Diagnosis plug ( line K )

1

5

Not connected

-

6

Not connected

-

7

Not connected

-

8

Idle switch

3

9

Signal oxygen rod

3

10

Signal oxygen rod

4

11

Valve potentiometer ( signal track 2 )

4

12

Valve potentiometer ( signal track 1 )

2

13

Sensor air temperature

1

14

Sensor engine temperature

1

15

Not connected

-

16

Permanent supply ( + )

clamp 30

17

Supply ( + ) after contact, relay R2

clamp 87

18

Mass

clamp 31

19

Control ignition coil ( cylinders 2 and 3 )

1

20

Mass

clamp 31

21

Signal rotation sensor

1

22

Control air conditioning

-

23

Mass

clamp 31

24

Speed-meter

-

25

Valve potentiometer ( supply + 5 V)

5

26

Not connected

-

Mass valve potentiometer

1

27

Mass engine temperature sensor

2

Mass air temperature sensor

4

28

Control relay fuel pump R1

clamp 86

29

Control canister purging valve

1

30

Control relay air conditioning R3

clamp 86

31

Control witness injection ( front panel )

-

32

Control idle regulator

1

33

Mass

clamp 31

34

Control idle regulator

2

35

Control injector

3

Table no. 1

DESCRIPTION OF THE SYSTEM