Rear Door Control Unit, Basic Function - GF72.29-P-9892A

Model all (CAR) 

Overview 

This document contains the following information:

• Location 
• Networking 
• Controlling functions 

Courtesy of MERCEDES-BENZ USA

Location 

The rear door control units are located in each case in the door module behind the door trim.

Networking 

Depending on the vehicle, the rear door control units can be differently connected to the network architecture of the vehicle:

• Directly via its own interface
• In master-slave-combination via the front door control units

Controlling functions 

The rear door control units have the following functions:

• Power window assembly.
• Central locking system.
• Side window roller blinds (vehicles with roller sun blinds in rear doors).
• Power closing function (vehicles with power closing function).

For the implementation of the respective function, the rear door control units evaluate - among other things - the following information:

• Terminal status of terminal 15.
• Lock/unlock central locking system request.
• PRE-SAFE® adjustment request (vehicles with PRE-SAFE® System).
• Convenience feature request.
• Rain closing function request.
• Crash signal.
• Operating requests.
• Status of the microswitches in the door locks.
• Status of the power closing function microswitches (vehicles with power closing function).

The rear door control units actuate different actuators in the respective rear door and/or transmit the corresponding information and requests to the respectively affected systems. This includes:

• Door status (open/closed).
• Seat heating and seat climate control request (vehicles with seat heating and seat climate control in rear).
• Open/close roof roller sunblind request (vehicles with panoramic sliding sunroof).
• Power window assembly actuation.
• Rear passenger compartment side window roller sunblind motor actuation (vehicles with roller sun blinds in rear doors).
• Power closing function motor actuation (vehicles with power closing function).

The rear door control units also protect the respective power window motor against overheating.

The software simulates temperature characteristics depending on the operating time. The necessary parameters for this are stored in the respective rear door control unit.

If the overheating protection is triggered, the actuation of the affected power window motor is blocked for a minimum cooling time.

Exception: 

The overheating protection function does not operate during roof reversal (after a blockage is detected).

With automatic doors in the rear, an additional rear door control unit that controls the door drive system is fitted on each side of the vehicle.