Starting and Charging: Service and Repair

Replacing Wiring Harness Section For Engine (M62/S62)

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

Disconnect plug connections on DME control unit. This task is described in the section "Replacing control unit".

E39 only:







Disconnect plug connection (1) on temperature sensor for electronics box.
Release locks (2).
Remove strip (3) towards top.
Release nut (4) and remove grounding cable strap.
Disconnect remaining plug connections of engine wiring harness in electronics box.







Release retaining clips (1).


CAUTION!
The air duct can brake at the firewall if not carefully removed and installed.
Carefully twist air duct (2) upwards until it is no longer locked in firewall. Pull air duct (2) forwards and remove towards top.







Detach rubber strip (1).
Release fasteners (2).







Remove retaining clip (1).
Remove heater bulkhead (2 and 3).

E52 only:
Disconnect remaining plug connections of engine wiring harness in electronics box.
Remove left and right partition walls for equipment compartment.

E39 and E52:
Disconnect intake air manifold.







Disconnect plug connections (1).
Unclip cable (2) from cable guides.







Disconnect plug connections (1).
Unclip cable (2) from cable guide.







Disconnect plug connection for throttle actuator (1), idle speed control valve (2) and electric changeover valve (3).







Disconnect plug connection (1) for tank venting valve.


NOTE: For a better overview, the following work steps are shown on an engine that has been removed.







Disconnect plug connection (1) for left and right pulse generators for exhaust camshaft.
Disconnect plug connection (2) for left and right pulse generators for inlet camshaft.
Disconnect plug connection (3) for knock sensor pair from cable duct (4) on left and right.
Slacken screws.
Feed plug (1) through holder (5).







Unhook both cable ducts (1) from mounts and raise approx. 2 cm.

Installation:
Check seating of rubber grommets on ignition coil cable.
Unclip both cable strips (2), tilt up and tie back (e.g. to engine hood).







Disconnect plug connection (1) for throttle potentiometer on left and right.
Disconnect plug connections on ignition coils. This task is described in the section "Replacing ignition coils".
Remove underbody protection at front and rear.

E39 only:







Remove cable holders (1).
Disconnect plug connection for exhaust temperature sensor on left.


NOTE: The exhaust temperature sensor is omitted from September 2000.

Remove cable holder (2).
Disconnect plug connection for oxygen and monitor sensors on left and right.

E52 only:







Mark left and right plug connections (1 and 2) to avoid mixing up plugs.
Unclip left and right plug connections (1 and 2) from holders and disconnect.
Unclip cables from cable holders (3).


NOTE: The exhaust temperature sensor is omitted from September
2000.





Disconnect plug connection (1).
Unclip cable (2) from cable holders (3).

E39 and E52:







Disconnect plug from reversing light switch (1) and gear detection switch (2).







Unclip cable (1) from fixtures (2) on cross-member.







NOTE: For a better overview, this work step is shown without the exhaust system.


Unclip cable (1) from cable holder (2) on transmission housing.







Disconnect plug connection (1) on pulse generator.







Disconnect plug connection (1) on starter motor.
Unclip cable from cable guides (2).


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