Operation CHARM: Car repair manuals for everyone.

Principles of Operation (How Does It Work?)

Anti-Theft Perimeter Protection Feature
The anti-theft perimeter protection feature is controlled by the front electronic module (FEM), the rear electronic module (REM), and the remote keyless entry (RKE) (driver door module [DDM]) module. This feature is configurable to the FEM and REM. The alarm can be armed using the remote transmitter to the RKE (DDM) module which sends a message via the network link to the FEM, or by using the driver door lock switch. The FEM and REM will then monitor all features which will activate the alarm. These features are:
- All door ajar switches
- Hood and liftgate ajar switches
- Radio, and ignition switch, anti-theft switches
- diagnostic access to the SCP network

Additionally, a single security hardwire from the FEM to the REM is monitored for an open.

Once the alarm has been armed, if any of the above features receive any activation, the alarm will then activate the visual and audible alerts.