12 42 530 Removing and installing/replacing battery positive lead (between starter motor and alternator) (M57TU, M57T2)

Necessary preliminary tasks:

Read out fault memory of DME control unit
Switch off ignition
Disconnect battery negative lead

Follow instructions for disconnecting and connecting battery

Release nut and remove battery positive lead (2) from alternator.

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.

Tightening torque: 12 31 1AZ .

Fig 1: Identifying Battery Positive Lead From Alternator

Courtesy of BMW OF NORTH AMERICA, INC.

Slacken nut (1).

Tightening torque: 12 41 4AZ .

Detach battery positive lead (2) from starter motor and remove.

NOTE: For a better overview, this work step is shown from below. Carry out removal of battery positive lead from above.

Fig 2: Identifying Battery Positive Lead And Nut

Courtesy of BMW OF NORTH AMERICA, INC.

NOTE: Check stored fault messages.
Now clear the fault memory.