12 31 020 Removing and installing/replacing alternator (M57TU, M57T2, M47T2)

Necessary preliminary tasks

Disconnect battery negative lead
Remove fan cowl
Remove DRIVE BELT for alternator
Release power steering pump and place to one side, secure against falling down/off
Release coolant expansion tank and place to one side, secure against falling down/off

Slacken nut (1).

Unlock connector (2) and remove.

Installation:

The positive power supply of the preheating control unit is also connected to terminal 30 of the alternator. This lead must be connected without fail, otherwise the preheating system will fail.

Fig 1: Identifying Slacken Nut And Connection

Courtesy of BMW OF NORTH AMERICA, INC.

Release screw and remove idler pulley (1).

Unfasten screws.

Pull alternator (2) upwards to remove.

Fig 2: Identifying Idler Pulley And Idler Pulley

Courtesy of BMW OF NORTH AMERICA, INC.

Installation:

Check function of DDE.