CTD Circuit Description

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

BODY CONTROL MODULE (BCM)
The CTD system is an internal function of the Body Control Module (BCM) which utilizes class 2 serial data and various switch input information to perform CTD functions. When the BCM detects an unauthorized entry, it activates the horns and exterior lamps. When the BCM detects an unauthorized entry, the BCM enters the alarm mode. The BCM activates the horns and exterior lamps for 2 minutes. This is followed by a three minute time-out with the horn no longer active.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.

DOOR AJAR SWITCHES
The CTD system uses the door ajar switches in the door lock assemblies as one method to activate the alarm. The body control module (BCM) monitors all door ajar switches via a discrete input from each door ajar switch, including the rear compartment. If the BCM receives a ground signal from a door ajar switch when the CTD system is armed, the BCM activates the alarm.

POWER DOOR LOCK SWITCHES
The power door lock switches are used to either arm or disarm the CTD system. Pressing the lock position will cause the CTD to arm after all doors are closed and the 30 second delay period has elapsed. Pressing the unlock position will disarm the CTD system.

INPUTS
The BCM monitors the following inputs:
^ Driver and passenger door ajar switches
^ Driver and passenger power door lock/unlock switches
^ Rear compartment ajar switch
^ Transmitter LOCK/UNLOCK buttons (internal function of the BCM)
^ Passlock(TM) Status (the BCM uses the Passlock(TM) status for disarming the system or silencing and alarm when the correct key is used)

OUTPUTS
The BCM controls the following:
^ The horn relay.
^ The exterior lights.