12 42 500 Replacing battery positive lead (between starter, alternator and battery positive terminal)

Necessary preliminary tasks: 

• Read out fault memory of DME control unit
• Switch off ignition
• Disconnect Battery Negative Lead 
• Remove Sound Generator 
• Remove Lock Bridge 
• Disconnect battery positive lead from battery positive terminal. For tightening torque refer to 61 21 1AZ  in 61 21 BATTERY WITH TERMINAL
• Unlock plug on bulkhead and disconnect

Release clamps (1) and detach air intake hose (2).

Fig 1: Clamps And Air Intake Hose

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Unlock plug (1) and remove.

Release nut and disconnect battery positive lead (2).

For tightening torque refer to 12 41 2AZ  in 12 41 STARTER MOTOR AND MOUNTING PARTS .

Fig 2: Plug, Retaining Nut And Battery Positive Lead

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Release screw and remove holder (1).

Fig 3: Retaining Screw And Holder

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Unlock plug (1) and remove.

Release nut and disconnect battery positive lead (2).

For tightening torque refer to 12 31 2AZ  in 12 31 ALTERNATOR WITH DRIVE AND MOUNTING PARTS .

Fig 4: Battery Positive Lead, Retaining Nut And Plug

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Release bolts.

For tightening torque refer to 12 51 3AZ  in 12 51 PLUG CONNECTIONS, TERMINALS, LOOSE PARTS .

Feed out air wiring harness (1) and remove.

Fig 5: Air Wiring Harness And Mounting Bolts

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