12 42 550 Replacing positive battery cable lead between starter motor, alternator and positive battery connection point (N74)

Necessary preliminary tasks:

Read out the fault memory of the DME control unit.
Switch off ignition.
Disconnect BATTERY EARTH LEAD
Remove catalytic converters. See CYLINDER 7-12 CATALYTIC CONVERTER and CYLINDER 1-6 CATALYTIC CONVERTER .
Remove INTAKE PLENUM .
Remove FRONT BULKHEAD SOUND INSULATION .
Remove INTAKE PORT on left and right

Fold back cover (1).

Release nut underneath. Remove positive battery cable lead (2) from positive battery connection point.

Tightening torque: see 3AZ in 12 42 ALTERNATOR LEAD .

Fig 1: Identifying Positive Battery Cable Lead And Cover

G08469644

Courtesy of BMW OF NORTH AMERICA, INC.

Unclip the positive battery cable (1) above the gearbox from the clamps (2).

Fig 2: Identifying Positive Battery Cable And Clamps

G08469645

Courtesy of BMW OF NORTH AMERICA, INC.

Feed out the vacuum hose (1) and remove.

Fig 3: Identifying Feed Out Vacuum Hose

G08469599

Courtesy of BMW OF NORTH AMERICA, INC.

Release positive battery cable from clamps (1) and expose.

Fig 4: Identifying Positive Battery Cable Clamps

G08469600

Courtesy of BMW OF NORTH AMERICA, INC.

Release positive battery cable from clamps (1) and expose.

Fig 5: Identifying Positive Battery Cable Clamps

G08469648

Courtesy of BMW OF NORTH AMERICA, INC.

Remove the cover (3) and undo the nuts underneath.

Tightening torque: see 1AZ in 12 42 ALTERNATOR LEAD .

Disconnect positive battery cable from alternator and feed out.

Fig 6: Identifying Alternator Cover, Plug And Screw

G08469629

Courtesy of BMW OF NORTH AMERICA, INC.

Release screws (1).

Tightening torque: see 2AZ in 12 41 STARTER MOTOR WITH MOUNTING .

Remove heat shield (2).

Fig 7: Identifying Heat Shield With Screws

G08469639

Courtesy of BMW OF NORTH AMERICA, INC.

Slacken nut (1).

Tightening torque: see 2AZ in 12 42 ALTERNATOR LEAD .

Undo positive battery cable from starter motor and remove.

Fig 8: Identifying Starter, Connector, Screw And Nut

G08469640

Courtesy of BMW OF NORTH AMERICA, INC.

NOTE: Reassemble the vehicle.

Check stored fault message.

Delete fault memory.