Ctd Circuit Description

The following is a description of each component used in the CTD system:

Door Lock Actuators
The CTD system uses the door jamb switches in the door lock assembly as one method to activate the alarm. The driver door module (DDM) monitors all door jamb switches via a discrete input or the door lock serial data (DLSD) from the other door modules. If the remote function actuator (RFA) module receives a class 2 message from the DDM that a door is open and the CTD system is armed, the RFA module activates the alarm.

Remote Function Actuator (RFA) Module
The CTD system is an internal function of the remote function actuator (RFA) module which utilizes class 2 serial data and various switch input information to perform CTD functions. When the RFA module detects an unauthorized entry it activates the horns and exterior lamps. The RFA module has 5 basic modes (disarmed, standby, delayed, armed, and alarm) for operating the CTD system. The different modes are described.
1. The RFA module has the CTD system in a disarmed mode until the following conditions are detected:
^ Ignition key turned to the OFF position.
^ Any door open.
^ Doors locked by either the power door lock switch or the LOCK button on the transmitter.
2. The RFA module enters the standby mode when the above conditions are detected. In standby mode the RFA module commands the instrument cluster to illuminate the SECURITY indicator via a descrete input. (If all the doors are closed and the LOCK button on the transmitter is used, the RFA module enters the delayed mode.
3. When the last door is closed, the RFA module enters the delayed mode for 30 seconds. In delayed mode the RFA module commands the instrument cluster to illuminate the SECURITY indicator via a descrete input.
4. After 30 seconds, the RFA module enters the armed mode. In armed mode the RFA module commands the instrument cluster to turn off the SECURITY indicator via a descrete input. Any forced entry activates the alarm mode.
5. When the RFA module detects a forced entry, the RFA module enters the alarm mode. The RFA module activates the horn and exterior lamps for 30 seconds. This is followed by a 3 minute time-out with the horn no longer active. If no new intrusions are detected after the time-out, the horn is not active. The system must be disarmed or the intrusion condition removed after the time-out for the system to exit alarm mode.

Important
The CTD system can be armed with the windows or sunroof open.

Inputs
The remote function actuator (RFA) module monitors the following inputs:
^ The door lock actuators, class 2 message from the Driver Door Module
^ The driver and passenger power door lock/unlock switches, class 2 message from the Driver Door Module
^ The front door lock cylinder disarm switches, class 2 message from the Driver Door Module
^ The rear compartment tamper switch
^ The transmitter LOCK/UNLOCK buttons

Outputs
The Remote Function Actuator (RFA) Module commands the following:
^ The horn relay
^ The Lamp Control Module (LCM), via a class 2 message