Checking Ignition Coils (Secondary Coil)

Checking ignition coils (secondary coil)

Carry out secondary voltage check using test adapter 12 7 040.







NOTE: The following checks can be carried out with the adapter kit:
- Secondary voltage check
- Comparison between ignition coils from different manufacturers
- Ignition coil faults
- Spark plug faults
- Injection system faults


CAUTION!
Observe safety precautions.







Connect special tool 12 7 043 (connecting cable) to special tool 12 7 041 (single adapter).







Special tool 12 7 041 (single adapter) for fitting onto ignition coil.


NOTE: When carrying out checks on compact ignition coils (e.g. M43), also use special tool 12 7 045.







Remove cover for ignition coils.







Observe safety precautions!
Switch off ignition.
Firing sequence 1-5-3-6-2-4.







Switch off ignition!
Mount special tool 12 7 041 on ignition coils and connect with special tool 12 7 043.







Connect DIS Tester with RZV connecting lead to last test adapter (RZV = static ignition distribution).
Connect trigger pliers of DIS tester to feed line on ignition coil of 1st cylinder.
- Select "Measurement".
- Select "Preset measurements".
Subsequent procedure in accordance with DIS instructions.







On vehicles with rodent protection:
Shown here on an M43 example.
Remove ignition lead of cylinder 1 from spark plug and fit special tool 12 7 030 between ignition lead of cylinder 1 and spark plug. Do not connect ground cable.
Connect trigger pliers of DIS Tester to special tool 12 7 030.







Follow instructions for troubleshooting with aid of adapter kit:
- Normal oscillogram MG12
- Ignition coil comparison MG12
- Ignition coil fault MG12
- Spark plug fault MG12
- Further fault patterns MG12
- Fault at injection system MG12