12 21 520 Replacing glowplug control unit (N47 D20 O 1 with SCR)

Necessary preliminary tasks:

Switch off ignition.
PARTIALLY detach rear acoustic cover.

Detach connector (1) from preheating control unit.

Release screw (2).

Tightening torque: 12 23 2AZ .

Remove preheating control unit (3).

Fig 1: Identifying Connector, Screw And Preheating Control Unit

Courtesy of BMW OF NORTH AMERICA, INC.

NOTE: If the preheating control unit is replaced, the preheating control service function must be performed using the diagnosis system after it is replaced.

Installation note:

Assemble engine.