Operation CHARM: Car repair manuals for everyone.

Locks: Description and Operation

CENTRAL LOCKING
The central locking system locks all vehicle doors if any door is locked from the inside or mechanically locked with the key from the outside. the master door lock switch on the instrument panel enables the operator to lock/unlock all doors.

REMOTE KEYLESS ENTRY
The SKREEM is a combination of the Remote Key-less Entry (RKE) module and the Sentry Key Immobilizer (SKIM) module. It is located behind the instrument cluster and has an antenna that mounts to the A-pillar.

AUTO DOOR LOCKS
Whenever the engine is started, the CTM receivers a message to lock all doors except the drivers door. This is accomplished through a relay. The relay is controlled by the Instrument Cluster which receives a command from the ECM.

ACCIDENT RESPONSE
The CTM is hardwired to the Airbag Control Module through the Enhanced Accident Report Driver circuit. Anytime the vehicles airbags are deployed, the CTM will unlock all doors and a "crash" DTC will be stored in memory. The door locks will be inoperative until that code is cleared.