12 51 001 Replacing Wiring Harness Section for Engine

12 51 001 Replacing Wiring Harness Section For Ignition Coils On Right Or Left (N74)







IMPORTANT: Read and comply with notes on protection against electrostatic discharge (ESD protection).







Necessary preliminary work:
- Read out fault memory of DME control unit
- Turn off ignition
- Disconnect battery negative lead
- Remove charge air cooler on left or right







Picture shows the left side, the procedure for the right side is identical.
Release screws (1).
Tightening torque 12 90 2AZ.
Remove electronics box cover (2).







Picture shows the left side, the procedure for the right side is identical.
Unlock all connectors (1) from control unit and disconnect.
Unclip grommet hold-down device (2) and remove.
Release rubber grommets (3) from electronics box. Lay wiring harnesses to one side.

Installation note:
Make sure grommets are correctly seated (watertightness).







Picture shows the left side, the procedure for the right side is identical.
Release screw (1).
Tightening torque 12 52 5AZ.
Unfasten screws (2).
Tightening torque 12 52 5AZ.
Unlock all connectors from injectors and ignition coils and detach.
Feed out air wiring harness (3) and remove.







Release wiring harness if necessary from existing clips and clamps







Installation note:
Check wiring harness installation arrangement.
Check plug connections for correct seating.
Check stored fault message.
Delete fault memory.