12 42 500 Replacing positive battery cable between starter motor, alternator and positive battery connection point (S55)

Necessary preliminary work: 

• Read out the fault memory of the DME control unit.
• Switch off ignition.
• Disconnect NEGATIVE BATTERY CABLE .
• Remove CARBON STRUT .
• Remove SOUND INSULATION bulkhead upper part, center.
• Remove AIR INTAKE PLENUM .

Removal: 

Release screw (1).

Remove positive battery cable from positive battery connection point.

Detach positive battery cable from the partition wall (2).

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Slacken nut (1).

Disconnect positive battery cable from starter motor.

Remove protective cap and release nut (2) underneath.

Disconnect positive battery cable from alternator.

Detach positive battery cable from the clamps.

Feed out positive battery cable and remove.

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Installation: 

Feed in and install positive battery cable.

Connect positive battery cable to the starter motor.

Tighten nut (1).

Tightening torque: 12 42 2AZ .

Connect positive battery cable to alternator.

Tighten nut (2).

Tightening torque: 12 42 1AZ .

Install protective cap.

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Mount positive battery cable at the remote positive terminal.

Tighten screw (1).

Tightening torque: 12 42 3AZ .

Mount positive battery cable on the partition wall (2).

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Installation note: 

Check wiring harness installation arrangement.

Check stored fault messages.

Delete the fault memory.

Required follow-up work 

• Install INTAKE PLENUM .
• Install CARBON STRUT .
• Install SOUND INSULATION on bulkhead upper part, center.
• Connect NEGATIVE BATTERY CABLE .