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Engine fails to start, quicktest

Engine fails to start, quick test

Diagnostic procedure

1. Check the fuses



- Check the following fuses:

maxi fuse 2

28 (control module supply, +30 circuit)

17 (control module supply, +15 circuit)

32 (fuel pump relay supply to fuel pump)

16 B (main relay supply to injectors and ignition discharge module)


Are the fuses intact?

yes

Continue with point 2.


no

Change any blown fuses. Then continue with point 2.


2. Check the CHECK ENGINE lamp (MIL)



- Ignition on.



- Check the fuel level.



- Check that the CHECK ENGINE lamp (MIL) lights up and stays on.


Is the CHECK ENGINE lamp on?

yes

The control module is activated. Continue with point 3.


no

No control module supply (+15 circuit). Rectify the fault.


no

The CHECK ENGINE lamp (MIL) shines weakly or flickers. No control module supply (+30 circuit) or ground connection. When this fault occurs a buzzing sound can also be heard from the main and fuel pump relays at the same time as the tachometer needle moves round the dial. Rectify the fault.


3. Check the main relay


Since the main relay supplies the injectors and ignition discharge module with power, check its operation as follows:


- Ignition switch in the OFF position



- Connect the test lamp to pins 10 and 6 of the ignition discharge module's connector.



- Remove fuse 28 for 5 seconds.



- Insert fuse 28.



- Ignition switch in ON position



- Check whether the test lamp lights up for about 6 seconds and then goes out.


Does the test lamp light up for 6 seconds?

yes

The main relay is OK. Continue with point 4.


no

Se


4. Run the starter motor when the test lamp has gone out


The test lamp should then light up again.

Test lamp on?

yes

The crankshaft position sensor is OK. Continue with point 5.


no

The control module receives no information from the crankshaft position sensor, see .


5. Check the fuel pump relay


Since the fuel pump relay supplies the fuel pump with power, check the operation of the fuel pump relay as follows:


- Ignition switch in the OFF position.



- Remove fuse 28 for 5 seconds.



- Insert fuse 28.



- Ignition switch in ON position



- Listen for the sound of the fuel pump working.


The fuel pump should run for 2 seconds.

Does the fuel pump work?

yes

The fuel pump relay is OK. Continue with point 6.


no

Se .


6. Final check



- Check the following: as in point 3, that the power supplied by the main relay reaches the injectors.



- that the ignition discharge module produces sparks.




- that fuel pressure is present.



Is power supplied to the injectors?

yes

The power supply is OK.


no

Check the leads up to crimped connection J67.




Does the ignition discharge module produce sparks?

yes

The ignition discharge module is OK.


no

Se




Is the fuel pressure adequate?

yes

The fuel pump is OK.


no

See Service Manual 2:3 "Fuel system and air induction system".