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12 51 001 Replacing Wiring Harness Section For Engine (S54)

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NOTE: Switch off ignition. Follow instructions for disconnecting and connecting battery. Refer to 12 00 ... INSTRUCTIONS FOR DISCONNECTING AND CONNECTING BATTERY . Disconnect and cover battery negative lead.

Preparatory tasks:

NOTES ON CHECKING IGNITION SYSTEM

Work step Note:
Unlock plug on idle-speed control valve and disconnect. Refer to 13 41 500 REPLACING IDLE-SPEED CONTROL VALVE .  
Unlock plug on throttle actuator and disconnect. Refer to 12 72 010 REMOVING AND INSTALLING/REPLACING THROTTLE ACTUATOR (S54) .  
Unlock plug on throttle potentiometer and disconnect. Refer to 13 63 555 REPLACING THROTTLE POTENTIOMETER (S54) .  
Unlock plug on solenoid valve for VANOS and disconnect. Refer to 11 36 010 REMOVING AND INSTALLING, SEALING/REPLACING VANOS ADJUSTMENT UNIT (S54 .  
Unlock connector strip of fuel injectors and disconnect. Refer to 13 64 501 REMOVING AND INSTALLING/REPLACING A FUEL INJECTOR (S54) . Follow removal instructions. Refer to 13 64 501 REMOVING AND INSTALLING/REPLACING A FUEL INJECTOR (S54) .
Disconnect plug of inlet camshaft sensor from connector strip. Refer to 12 14 523 REPLACING PULSE GENERATOR ON INLET CAMSHAFT (S54) .  
Unlock plug on oil pressure switch and disconnect. Refer to 12 61 280 REMOVING AND INSTALLING/REPLACING OIL PRESSURE SWITCH (S54) .  
Unlock plug on coolant temperature sensor and disconnect. Refer to 13 62 531 REPLACING COOLANT TEMPERATURE SENSOR (S54) .  
Unlock plug on knock sensors and disconnect. Refer to 12 14 600 REPLACING KNOCK SENSOR(S) (S54) .  
Unlock pulse generator plug on exhaust camshaft and disconnect. Refer to 12 14 524 REPLACING PULSE GENERATOR ON EXHAUST CAMSHAFT (S54) .  
Unlock plug on alternator and disconnect. Refer to 12 31 020 REMOVING AND INSTALLING/REPLACING ALTERNATOR (S54) . Detach battery positive lead at alternator. Remove oil lines. Note tightening torque. Refer to 12 31 020 REMOVING AND INSTALLING/REPLACING ALTERNATOR (S54) .
Unlock plug on oil level switch and disconnect. Refer to 12 61 285 REPLACING LEVEL SWITCH FOR ENGINE OIL (M62, M54, S54, M56) . Do not remove oil level switch.
Detach battery positive lead and control lead from starter motor. Refer to 12 41 020 REMOVING AND INSTALLING/REPLACING STARTER MOTOR (S54) . Note tightening torque. Refer to ENGINE ELECTRICAL SYSTEM - TIGHTENING TORQUES .
Unlock pulse generator plug for crankshaft on distributor housing and disconnect. Refer to 12 14 521 REPLACING PULSE GENERATOR ON CRANKSHAFT (S54) .  
Unlock plug connections in electronics box and disconnect:
  • Remove electronics box cover.
  • Do not remove control unit.

Release screw and remove manifold support (1).

Installation: 

To avoid manifold torsion stress, secure manifold support with I screw but do not tighten down screw. Only tighten down screw

Fig 1: Locating Manifold Support
G03118190Courtesy of BMW OF NORTH AMERICA, INC.

Release screws and remove cable duct (1).

Fig 2: View Of Cable Duct
G03118191Courtesy of BMW OF NORTH AMERICA, INC.

Detach sealing strip (1).

Turn toggle (2) through 90 degrees.

Remove partition wall for equipment compartment (3).

Release nut.

Remove cable housing (4).

Installation: 

Ensure profile seals are correctly positioned.

Fig 3: Identifying Cable Housing
G03118192Courtesy of BMW OF NORTH AMERICA, INC.