After a loss of battery power has been restored the theft deterrent control module will perform a check on the stored vehicle identification number (VIN). If the VIN is CORRECT, the theft deterrent control module will run the VIN Timer for a programmable length of time, typically 10 minutes. The theft deterrent control module will send a message via the serial data circuit to the instrument panel cluster (IPC) to illuminate the SECURITY indicator. After the VIN Timer has timed out, the security indicator will turn OFF. If the VIN is INCORRECT, the theft deterrent control module will send the fuel disable password to the ECM via the serial data circuit. The VTD system considers this to be a tamper and will not allow the vehicle to start. The theft deterrent control module will send a message via the serial data circuit to the instrument panel cluster (IPC) to flash the SECURITY indicator.
The ignition is ON.
• | The VIN check flag of the theft deterrent control module is true. |
• | The theft deterrent control module has determined that the battery has been reconnected after a disconnect. |
• | The vehicle will not start. |
• | The theft deterrent control module sends the fuel disable message via the serial data circuit to the ECM. |
• | The theft deterrent control module sends a message to the instrument panel cluster (IPC) to flash the SECURITY indicator. |
• | The Theft Deterrent control module clears the current DTC when the correct VIN information is present. |
• | The DTC can be cleared by using a scan tool. |
The VIN information is stored during the Setup New VTD Module procedure on a GM SPO replacement part. When the manufactures enable counter (MEC) is equal to 0 the VIN information cannot be changed.
The number below refers to the step number on the diagnostic table:
Step | Action | Yes | No |
---|---|---|---|
Schematic Reference: Theft Deterrent System Schematics Connector End View Reference: Theft Deterrent System Connector End Views | |||
1 | Did you perform the Theft Deterrent Diagnostic System Check? | Go to Step 2 | |
Important: If a 10 Minute or 30 Minute Re-Learn Procedure is perform, all keys not learned at that time will be erased and will not be recognized. Perform the Adding Keys procedure on all keys or instruct the customer how to perform the Adding Keys procedure. Refer to Adding Keys .
Did you complete the replacement? | Go to Step 3 | -- | |
3 |
Does the DTC reset? | Go to Step 2 | System OK |