12 42 550 Replacing positive battery cable lead between starter motor, alternator and positive battery connection point (N74)

Necessary preliminary tasks: 

• Read out the fault memory of the DME control unit.
• Switch off ignition.
• Disconnect BATTERY EARTH LEAD
• Remove catalytic converters. See CYLINDER 7-12 CATALYTIC CONVERTER and CYLINDER 1-6 CATALYTIC CONVERTER .
• Remove INTAKE PLENUM .
• Remove FRONT BULKHEAD SOUND INSULATION .
• Remove INTAKE PORT on left and right

Fold back cover (1).

Release nut underneath. Remove positive battery cable lead (2) from positive battery connection point.

Tightening torque: see 3AZ in 12 42 ALTERNATOR LEAD .

Fig 1: Identifying Positive Battery Cable Lead And Cover

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Unclip the positive battery cable (1) above the gearbox from the clamps (2).

Fig 2: Identifying Positive Battery Cable And Clamps

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Feed out the vacuum hose (1) and remove.

Fig 3: Identifying Feed Out Vacuum Hose

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Release positive battery cable from clamps (1) and expose.

Fig 4: Identifying Positive Battery Cable Clamps

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Release positive battery cable from clamps (1) and expose.

Fig 5: Identifying Positive Battery Cable Clamps

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Remove the cover (3) and undo the nuts underneath.

Tightening torque: see 1AZ in 12 42 ALTERNATOR LEAD .

Disconnect positive battery cable from alternator and feed out.

Fig 6: Identifying Alternator Cover, Plug And Screw

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Release screws (1).

Tightening torque: see 2AZ in 12 41 STARTER MOTOR WITH MOUNTING .

Remove heat shield (2).

Fig 7: Identifying Heat Shield With Screws

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Slacken nut (1).

Tightening torque: see 2AZ in 12 42 ALTERNATOR LEAD .

Undo positive battery cable from starter motor and remove.

Fig 8: Identifying Starter, Connector, Screw And Nut

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Check stored fault message.

Delete fault memory.