12 13 009 Checking ignition coils (secondary coil)

Special tools required:

12 7 040
12 7 041
12 7 042
12 7 043
12 7 045
12 7 046
12 7 050

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

IMPORTANT: Observe safety precautions.
Switch off ignition.

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

Fig 1: Identifying Test Adapter (Special Tool)

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

Fig 2: Assembling Special Tool To Special Tool

NOTE: Checks on engines with single-spark ignition coils:
Special tool 12 7 041 (single adapter) in conjunction with special tool 12 7 045 for fitting onto ignition coil.

Fig 3: Identifying Special Tool

Remove cover for ignition coils.

Version with single-spark ignition coils:

Mount special tool 12 7 041 on ignition coils and connect to special tool 12 7 043.

Fig 4: Mount Special Tool On Ignition Coils And Connecting To Special Tool (Single-Spark Ignition Coils)

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.

Fig 5: Connecting DIS Tester With RZV Connecting Lead

Version with rod-type ignition coils:

Unlock plug on rod-type ignition coil and disconnect.

Remove rod-type ignition coil, connect special tool 12 7 050 (adapter cable) to spark plug and ignition coil, connect ignition coil to engine wiring harness.

Carry out measurements following DIS instructions.

Fig 6: Connecting Special Tool To Spark Plug And Ignition Coil (Rod-Type Ignition Coils)

Version with ignition coil block:

Raise cover on ignition coil block slightly and fit special tool 12 7 046.

Connect special tool 12 7 046 to adapter cable 12 7 042 and then to Tester.

Fig 7: Connecting Special Tool To Adapter Cable And Tester (Ignition Coil Block)

NOTE: The adapter cable 12 7 042 is located in the case of the adapter kit 12 7 040.

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