71 60 100 Removing and installing/replacing control unit for trailer tow hitch unlocking

WARNING: This page is about a different car, the 2010 BMW 550i, 2009 BMW 550i, and 2008 BMW 550i. However, it is still accessible from the selected car via links, so may be relevant.

Necessary preliminary tasks:

Open luggage compartment floor trim panel . See 51 47 101 REMOVING AND INSTALLING/REPLACING LUGGAGE COMPARTMENT FLOOR TRIM PANEL .
Remove spare wheel
Remove cover for control units

IMPORTANT: Depending on the equipment specification, the position of the control unit for trailer tow hitch unlocking (2) can vary.

Remove control unit (2) and disconnect plug connection (1).

Fig 1: Identifying Control Unit And Plug Connection

Courtesy of BMW OF NORTH AMERICA, INC.

Replacement:

A control unit of the fully automatic trailer tow hitch with is not initialized indicates this by way of the LED in the button.

Initialization sequence:

If necessary, connect battery charger
Ignition off
Rear lid open
Press and hold down button for fully automatic trailer tow hitch

The ball hitch must in the process be pivoted at least once completely from one end stop to the other.

If initialization is successful and the ball hitch is in an end position, the LED on the button is permanently lit green.