Grand Cherokee 2WD L6-4.0L VIN S (1997)
Keyless Entry Receiver: Description and Operation
SYSTEM OPERATION
The Remote Keyless Entry (RKE) receiver is a radio frequency unit contained in the Passenger Door Module (PDM). The PDM also contains the
program circuitry for the RKE system. The PDM is located inside the passenger side front door, and is secured to the door trim panel.
The RKE receiver is energized by one of up to three messages from the RKE transmitter; Unlock, Lock, or an optional Panic. The PDM circuitry
responds to these messages to lock or unlock the power lock motors that it controls. The PDM circuitry also puts Lock, Unlock, and the optional
Panic messages on the Chrysler Collision Detection (CCD) data bus.
These messages will result in the Driver Door Module (DDM) locking or unlocking the driver side front door, and/or the Body Control Module
(BCM) initiating the proper Horn Chirp, Illuminated Entry, and Vehicle Theft Alarm functions. If the vehicle is equipped with the optional
memory system, the proper CCD Unlock message will also result in the DDM initiating its memory recall functions.
For diagnosis of the RKE receiver, the PDM, the DDM, or the CCD data bus, refer to the proper Computers and Control Systems/Body Control
Module/Testing and Inspection Procedures. The RKE receiver is only serviced as a unit with the PDM and, if faulty or damaged, the PDM unit
must be replaced.
