Diesel Data: Automotive Repair

Body Control Systems: Description and Operation

MODULE CONTROLLED FUNCTIONS

The multifunction modules consist of the following:
- generic electronic module (GEM)

PRINCIPLES OF OPERATION

The GEM constantly monitors its subsystems for concerns. If a concern is found in one of the subsystems, the GEM will record the concern in the form of a diagnostic trouble code (DTC). The ignition switch position is very important to the GEM function. Often times, erratic or unexpected GEM function can be traced to concerns with ignition switch inputs.