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The BCM contains the logic of the PASS-Key II system. The BCM has inputs from the battery, ignition circuits, key resistor, shock sensor, and door lock, door jamb and hatch switches. The BCM has outputs to the starter enable circuit, the fuel enable circuit, the security lamp circuit, and the remote hatch release. The BCM also controls power locks, interior lamps, horn chirps and parking lamp flashes for locking and arming functions. The BCM has some diagnostic features, including diagnostic trouble codes.
The fuel enable circuit is an output from the BCM and an input to the PCM. When the BCM senses the proper resistance at the ignition key, it will output a signal to the PCM. If the BCM does not see the proper resistance at the ignition key, it will not output the signal to the PCM.
The "SECURITY" Indicator is controlled directly by the Body Control Module. The following describes the modes of indicator operation: