C 3500 HD Truck 2WD V8-8.1L VIN G (2002)
Engine Control Module: Description and Operation
Theft Systems
The Powertrain Control Module (PCM) contains the remainder of the logic of the theft deterrent system. If a class 2 message containing a valid
password is received from the Passlock(TM) Module, the PCM will continue to allow the fuel injectors to operate. The PCM will allow the fuel injectors
to operate until it decides there is no valid password coming from the Passlock(TM) Module. If the PCM does not receive a class 2 message, or receives
a class 2 message with an incorrect password, the engine will crank and will not run or will start and stall immediately.