System Operation

SYSTEM OPERATION
The PASS-Key II(R) system is designed to prevent the engine from starting if the proper resistance is not sensed from the ignition key. Of the 15 key codes (resistance values) available, only one will work with each CCM. Once the key code is programmed into the Central Control Module (CCM), the resistance value is stored in a non-volatile memory.

The PASS-Key II(R) system prevents the engine from starting by controlling the starter enable relay and the PCM fuel enable input. If the PCM does not sense the proper pulse width modulated (PWM) signal in the fuel enable input, it will not provide fuel to the engine.

If the wrong resistance value is sensed when the ignition switch is in the "ON" position, the CCM will not ground the starter enable circuit and will not output the fuel enable PWM signal for approximately three minutes. This prevents the engine from starting and discourages the thief from trying key codes (resistance values) at random.

If the correct resistance value is sensed when the ignition switch is in the "ON" position, the CCM will ground the starter enable circuit and output the fuel enable PWM signal. This will allow the engine to start normally.