Powertrain Control Module (PCM)

Powertrain Control Module (PCM) (Under RH Side Of Instrument Panel):

The Powertrain Control Module (PCM) communicates with the Instrument Cluster via serial data over the UART serial data bus, CKT 800. When the Instrument Cluster has determined a Passed-Theft condition, it sends a coded password to the Powertrain Control Module (PCM). Upon receipt of the correct password, the PCM enables the fuel injection system. allowing the vehicle to operate correctly. Please note, the Powertrain Control Module (PCM) may allow the car to start and quickly stall during a Failed-Theft condition.

There are two ways the Powertrain Control Module (PCM) may enter a Tamper Mode; a bad timing cycle, or an incorrect password. If a password is not received from the Instrument Cluster within a preset time window, the Powertrain Control Module (PCM) will enter a Short Tamper Mode during which the Powertrain Control Module (PCM) will not allow the car to operate for four (4) seconds. If the password is incorrect, the Powertrain Control Module (PCM) will enter the LONG TAMPER MODE. In this mode, indicator will flash and the Fuel Injectors will be shut off for approximately ten (10) minutes. Again, the vehicle may start, but the engine will quickly stall due to fuel cut-off.

In the event of an open in serial data between the Instrument Cluster and the Powertrain Control Module (PCM), the Powertrain Control Module (PCM) will become fail-enabled if the car has already passed theft for that ignition cycle (i.e. the engine is running). In this event, the THEFT SYSTEM indicator will light continuously and the Powertrain Control Module (PCM) will become fail-enabled for future ignition cycles. If a failure in serial data occurs before

the ignition cycle, when the Powertrain Control Module (PCM) is not fail-enabled, the Powertrain Control Module (PCM) will never receive a valid password to enable continued use of the Fuel Injectors.