FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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Vehicle/Powertrain Control Module

The VCM/PCM communicates with the Passlock(TM) Module over the Class 2 serial data line. When the Passlock(TM) Module determines a no start condition, it sends a Class 2 serial data password to the VCM/PCM in order to disable the fuel injection system. If the Passlock(TM) Module receives the expected voltage from the Passlock(TM) Sensor, the Passlock(TM) Module sends a Class 2 serial data password to the VCM/PCM in order to enable the fuel injection system. The VCM/PCM then allows the vehicle to start correctly. If the Class 2 serial data password from the Passlock(TM) Module to the VCM/PCM is not within the Vehicle Security Status Message, the fuel injectors will shut OFF during a start attempt. The SECURITY telltale will be ON STEADY for approximately 10 minutes and then turns OFF. If the VCM/PCM does not receive the same password from the Passlock(TM) Module as the last learned one, the vehicle will Start and quickly stalls due to the Fuel Lock-out.