Coil Connector Pigtail Assembly: Service and Repair

Replacing Wiring Harness Section For Ignition Coils (M54)

Interrogate fault memory of DME control unit.
Switch off ignition.
Follow instructions for disconnecting and connecting battery.
Disconnect battery negative lead from battery.

E53 only:
Remove heater bulkhead.

Z3, E39, E46, E53:
Remove cover for ignition coils.
Detach plug of wiring harness for ignition coils from DME control unit. This operation is described in the section
"Replacing control unit". Disconnect plug connection of wiring harness for ignition coils in electronics box.


NOTE: Do not remove DME control unit.







Detach grounding strap (2) of cable duct from connecting plate of ignition coils between cylinders 2 and 3.







Unlock plug (1) and detach from ignition coils.
Unlock cable strip (2) and remove towards top.







E53 only:
Remove water reservoir for windshield washer system.
Remove cable (1) with profile seal from partition wall (3).
Unclip cable (2) from partition wall (3).
Release screw connection of partition wall (3) with body.
Remove partition wall (3).







Pull profile seal (1) out of electronics box.
Release locks (2).
Remove strip (3).
Pull out profile seal (4).

Installation Note: To prevent leaks, you must install profile seals (1 and 4) correctly.







E46 and Z3 only:


NOTE: Shown on the E46. The same procedure applies to the Z3.


Pull off sealing strip (1).
Remove cable (3) together with profile seal (2) from partition wall towards top.

Installation Note: To prevent leaks, you must install profile seal (2) correctly.







E39 only:
Release locks (1).
Remove cable (3) together with profile seal (2) from partition wall towards top.

Installation Note: To prevent leaks, you must install profile seal (2) correctly.

Z3, E46, E53 and E39:


NOTE:
Interrogate fault memory of DME control unit.
Check stored fault messages.
Rectify faults.
Then clear fault memory.