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Universal Theft Deterrent (UTD)

The UTD is armed and disarmed through a discrete input to the PZM. The UTD system detects unauthorized vehicle entry. UTD attempts to deter theft by cycling the horns and the exterior lamps on and off. The LTD has eight states of operation:
^ Off state - In the off state the ignition switch is not in "LOCK" and all doors are Closed. In this state, the LTD commands the security indicator off.
^ Idle state - In the Idle state the ignition switch is not in "LOCK" and any door is open. In this state, the LTD commands the security indicator off.
^ Disarmed state - In the disarmed state the ignition switch is m LOCK" and all doors are Closed. In this state, the UTD commands the security indicator off.
^ Ready To Arm state - In the Ready To Arm state the ignition switch is in "LOCK" and any door is open. In this state, the UTD commands the security indicator to flash to inform the driver that the vehicle is not in the process of arming and is in an unprotected state. The Ready To Arm state is the state in which the sequence of events to arm the LTD begins.
^ Arm Initiated state - In the Arm Initiated state the ignition switch is in "LOCK," any door is opened and the sequence of events needed to Allow the UTD to arm has been completed. In this state, the UTD commands the security indicator on to inform the driver that the UTD is ready to arm.
^ Arm Delay State - In the Arm Delay State, the state between the Arm Initiated and Armed states, the ignition switch is in "LOCK." The Arm Delay state is entered upon completion of the sequence of events needed to Allow the UTD to arm. In this state, the UTD commands the security indicator on to tell the driver that the UTD is about to be armed.
^ Armed state - In the Armed state the UTD monitors the door jamb switches, the state of the ignition, the trunk tamper switch and the vehicle's battery voltage inputs for security violations. In this state, the UTD commands the security indicator off, signifying that the UTD has been armed.
^ Alarm state - The Alarm state is the state entered after a violation of the inputs monitored in the Armed state has been detected. In this state, the UTD system commands the vehicle Alarm which consists of turning the exterior lamps and horn on and off.