Control Modules In Rear Doors (Does Not Apply To The C30).

Fig 1: Identifying Control Modules In The Rear Doors

Courtesy of VOLVO CARS CORPORATION

The left rear door module (LDM) and right rear door module (RDM) are identical and only manage the functions for the power windows and door locks in each door.

The control modules are positioned in their respective doors. The control modules are integrated with the power window lift motors. The control modules must also be replaced when replacing the power window lift motors.

There are two types of control module, Standard and High. The difference between the variants is that Standard does not have deadlocks or child-proof locks.

The left rear door module (LDM) and right rear door module (RDM) communicate with directly connected components and with the control module for the front door on the relevant side of the vehicle via LIN-communication.

Both control modules check activations and input and output signals via an integrated diagnostic system. A diagnostic trouble code (DTC) is stored if either of the control module detects a fault. The diagnostic trouble codes (DTCs) for the control modules in the rear doors are stored in the respective control module in the front doors.

Any diagnostic trouble codes (DTCs) are stored in the relevant control module in the front doors. The data can be read off.

A simple way to ensure that the control modules are powered and grounded is to activate one of the functions that are operated via the switches on the control panels in the respective door. The control module is powered and grounded if any of the functions are working.

For further information, also see SIGNALS .