12 51 100 Replacing wiring harness section for ignition coils (M54)

WARNING: This page is about a different car, the 2005 BMW Z4, 2004 BMW Z4, and 2003 BMW Z4. However, it is still accessible from the selected car via links, so may be relevant.

Necessary preliminary tasks:

Read out fault memory of DME control unit
Switch off ignition
Disconnect battery negative lead from battery.
Follow Instructions For Disconnecting And Connecting Battery .
Remove cover for ignition coils

Unfasten screws.

Open cover (1) of electronics box and remove.

Fig 1: Removing Electronics Box Cover

Courtesy of BMW OF NORTH AMERICA, INC.

Unlock plug (1) and detach from DME control unit.

Unlock plug (2) and remove.

Lift wiring harness with profile seal (3) out of electronics box.

Installation:

To prevent leaks, you must install profile seal (3) correctly.

Fig 2: Removing Wiring Harness With Profile Seal From Electronics Box

Courtesy of BMW OF NORTH AMERICA, INC.

Unlock plug retainer (1) of ignition coil and disconnect plug.

NOTE: This procedure is applicable to all ignition coils.

Release nuts and remove grounding cable.

Unclip cable duct (2).

Unclip wiring harness (3) and remove.

Fig 3: Removing Wiring Harness

Courtesy of BMW OF NORTH AMERICA, INC.

NOTE: Now clear the fault memory.