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Security Lamp/Indicator: Description and Operation

SECURITY INDICATOR
The instrument panel cluster (IPC) illuminates the SECURITY indicator as determined by the vehicle theft deterrent (VTD) system. The IPC receives a message via the serial data circuit from the theft deterrent control module requesting illumination. The VTD system requests the IPC to illuminate the indicator only when the ignition is ON. The VTD system uses the indicator as a malfunction indicator. For vehicle theft deterrent (VTD) information, refer to Vehicle Theft Deterrent (VTD) Description and Operation.

The SECURITY indicator on the instrument cluster is controlled by both the VTD system and the CTD system. The SECURITY indicator is an LED on the instrument cluster which illuminates the word SECURITY. The SECURITY indicator is controlled by the body control module grounding the security indicator control circuit.
- The VTD system commands the instrument cluster to control the indicator only when the ignition switch is ON. The VTD system uses the indicator as a malfunction indicator.
- The CTD system commands the instrument cluster to control the indicator only when the ignition switch is OFF. The CTD system uses the indicator to identify system status.

SECURITY INDICATOR OPERATION
The theft deterrent control module can command the instrument cluster to illuminate the SECURITY indicator only when the ignition key is in the ON position. If the PCM loses communication with the theft deterrent control module, the instrument cluster will also detect the loss of communication and will illuminate the SECURITY indicator. The SECURITY indicator can indicate both malfunctions, Indicator on steady and tamper, Indicator flashing. A flashing indicator indicates unauthorized operation. Under the following conditions the SECURITY indicator may be commanded to illuminate.

SECURITY Indicator Illuminates when Engine is Running
If the theft deterrent control module is unable to measure the ignition key transponder value or the PCM loses communication with the theft deterrent control module while the engine is running, the indicator will be illuminated.

SECURITY Indicator Illuminated and Engine Does Not Start
If the theft deterrent control module was unable to measure the ignition key transponder value or the PCM has detected a problem with the theft deterrent system. The VTD system is in Learn Mode. Refer to Programming Theft Deterrent System Components.

SECURITY Indicator Flashes and Engine Does Not Start
The theft deterrent control module has measured an incorrect transponder value, the calculation to the challenge is incorrect or the PCM has lost communication with the theft deterrent control module, The VTD system considers this a tamper condition. The VTD indicator will flash.