12F400

The connections of the fuel injector of cylinder 4 have a short circuit to each other.


Possible cause:

- Y76/4 (Cylinder 4 fuel injector)
Affected functions:

- Power generation

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Test 1: Check internal resistance of component Injector.

Test 2: Test wiring for Open circuit.

1. Check internal resistance of component Injector.
Check internal resistance of component Y76y4 (Fuel injector cylinder 4).
Special tools

- Adapter cable220 589 00 99 35
Test sequence

- Switch off ignition.
- Detach coupling at component Y76y4 (Fuel injector cylinder 4).
- Connect adapter cable no. 220 589 00 99 35 at component Y76y4 (Fuel injector cylinder 4).
- Measure resistance with multimeter between sockets (Y76y4) 1 and (Y76y4) 2
Specified value

- Resistor[150...210]kohms
Question

- Is the measurement value OK?


YES
The measurement value is OK.Further procedure

- If the case of stored faults which high fault frequency counter or in the case of customer complaints, inspect electric cables and connections for loose contact and corrosion.
- Test cables to component Y76y4 (Fuel injector cylinder 4) for open circuit.
End of test

NO
The measurement value is not OK.Possible cause and remedy

- Component Y76y4 (Fuel injector cylinder 4) is defective.
End of test

2. Test wiring for Open circuit.
Test cable to component Y76y4 (Fuel injector cylinder 4) for short circuit to each other.
Special tools

- Test cable 266 589 01 63 00
- Socket box 129 589 00 21 00
Test procedure Y76y4 (Fuel injector cylinder 4)

- Switch off ignition.
- Detach coupling at component Y76y4 (Fuel injector cylinder 4).
- Disconnect the socket M at control module N3/9 (CDI control unit).
- Connect 126-pole socket box at engine wiring harness.
- Measure resistance with multimeter between sockets (M.51) 51 and (M.3) 3 of the 126-pole socket box tester.
Specified value

- Resistor infinite ohms
Question

- Is the measurement value OK?


YES
The measurement value is OK.Plug in the socket at component Y76y4 (Fuel injector cylinder 4).End of test

NO
The measurement value is not OK.Further procedure

- Test cables and connections, rectify any short circuit.
End of test