Alternator: Service and Repair

12 31 020 - Removing and installing or replacing alternator (S65)





Necessary preliminary tasks:
- Switch off ignition
- Follow instructions for disconnecting and connecting battery 12 00 ... Instructions For Disconnecting and Connecting Battery
- Disconnect battery negative lead 61 20 900 Disconnecting and Connecting Battery Negative Lead and cover
- Remove air filter housing Service and Repair
- Remove underbody protection Removing and Installing/Replacing Front Underbody Protection
- Remove alternator drive belt Service and Repair





Release screws.
Unclip hoses from hose holders on radiator.
Carefully press leads (1) to one side.





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





Unlock plug (1) and remove.
Release nut (2), remove battery positive lead from alternator.
Tightening torque 12 31 1AZ Specifications.
Pull alternator (3) upwards to remove.
Add final details to vehicle.
Read fault memory.