Crankshaft Position Sensor: Service and Repair

Replacing Impulse Sensor (M52, S50US, S52)

Interrogate fault memory of DME control unit.
Switch off ignition.







Version 1:
Impulse sensor on front vibration damper:
Unfasten hydraulic line on VANOS adjustment unit.
Tightening Torque,
refer to Technical Data.







Unfasten screws and remove suspension lug.







Remove cable channel.







Unscrew screw. Remove pulse generator.

Installation:
After assembly, make sure that the lead from the pulse sensor does not contact the water pump drive gear.

Interrogate fault memory of DME control unit, check faults in memory, then cancel fault memory.







Installation location of plug connection:
Below manifold for intake air.
Remove hose for engine venting from valve cover.
Unfasten and remove oil filter cover and place cloth over unit to prevent dirt from entering the oil circuit.







Disconnect connector (2). Plug connection shown here with intake air manifold removed.







Version 2:
Impulse sensor below the starter motor:
Remove intake filter housing completely with mass air flow sensor and remove impulse sensor from top of vehicle.


NOTE: Shown here without throttle assembly for illustration purposes.







Unscrew bolt (1).
Remove impulse sensor (2).

Installation:
Check sealing ring on impulse sensor and replace if damaged.
Interrogate fault memory of DME control unit check faults in memory, then cancel fault memory.