The Thatcham Alarm monitors the vehicle doors, liftgate, hood, and the interior of the vehicle for unauthorized operation.
The vehicle doors, liftgate, and hood use ajar switches as inputs to the BCM to indicate their current status.
The interior of the vehicle is secured by the use of Intrusion Sensors. The Intrusion Sensors are used as inputs to
the interface module to report any motion in the interior of the vehicle. The interface module is located above the
courtesy lamp assembly in the headliner. The alarm activates by sounding the siren, and flashing the hazard lamps.
The Coupe uses an Ultrasonic System with two sensors facing rearward attached to the inside of the windshield
below the headliner and above the mirror.
The Roadster uses a Microwave Sensor located in the console below the cupholder.

Coupe The Coupe uses an Ultrasonic System with 2 Intrusion Sensors mounted on each side of the rearview mirror.
These sensors are connected to an interface module that is located above the courtesy lamp assembly in the headliner.
A defeat switch in the courtesy lamp assembly can disable the intrusion sensing function in the event that the
vehicle is parked for a short time with a pet/child/or object which could cause false alarms if left in the vehicle. The
interface module is connected to the standard alarm module. The Ultrasonic System provides full coverage of both
the passenger compartment, and the cargo area.
Roadster The Roadster, because the soft top can move with gusts of wind or external vibrations, the ultrasonic
solution is not practical. This vehicle uses a microwave sensor located in the console below the cupholder. This
sensor will provide full coverage of the passenger compartment. Similar to the Coupe, a means is provided to disable
the intrusion sensing portion of the alarm in the event that the vehicle remains occupied or is locked with the
top down.
The following procedure is used to arm and disarm the Thatcham Alarm:
Arming Before arming, all doors, liftgate, and the hood must be completely closed. The system can only be armed
by locking the doors with the RKE Transmitter.
Disarming To disarm the alarm system, use the RKE Transmitter or turn the Ignition Switch ON. This will disable the