2008 BMW M5 (E60) V10-5.0L (S85)FACTORY OEM SERVICE PROCEDURE

Alternator: Service and Repair




12 31 020 - Removing and installing/replacing alternator (S85)

Factory service manual diagram




Necessary preliminary tasks:
- Switch off ignition
- Follow instructions for disconnecting and connecting battery Instructions for Disconnecting and Connecting Battery
- Disconnect battery negative lead Disconnecting and Connecting Battery Negative Lead and cover
- Remove radiator Removing and Installing Radiator
- Remove alternator drive belt Replacing Alternator Drive Belt.

Factory service manual diagram




Unfasten screws.
Carefully press leads (1) to one side.

Factory service manual diagram




Unfasten screws.
Pull alternator (1) forwards until connections are accessible.

Factory service manual diagram




Unlock plug (1) and remove.
Release nut (2), remove battery positive lead from alternator.
Tightening torque 12 31 1AZ [1][2]Specifications.
Remove alternator (3).
Factory Service Tools

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.

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