Control Modules In The Rear Doors

Fig 1: Identifying Control Modules In Rear Doors

Courtesy of VOLVO CARS CORPORATION

The left rear door module (LDM) and right rear door module (RDM) are the same and only handle the power window and door lock functions in their respective door. The control modules are located in the respective rear door.

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 are stored in the relevant control module in the front doors. The data can be read off using the diagnostic tool.

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.