Passkey Systems

Passkey Wiring Schematic:

Passkey System Diagram - Typical:

CIRCUIT OPERATION

Resistor sensing contacts are located in the ignition key lock cylinder. These contact the key resistor pellet on the key when it is inserted. When the lock is rotated, battery voltage is applied through a fuse to the PASSkey(R) decoder module. The pellet resistance is then compared against a fixed resistance in the module.

If the key pellet is the proper resistance, terminal A3 is grounded, energizing the starter enable relay. At the same time, a signal is applied at terminal A2 to enable the Electronic Control Module (ECM). When this signal is received by the Electronic Control Module (ECM), it allows fuel injector pulses to begin.

If the key resister pellet is the wrong value, the PASSkey(R) decoder module will shut down for 2 to 4 minutes. During this interval there will be no output at terminals A3 or A2.

If the ignition switch is turned on again during this interval, the timer will remain shut down for another 2 to 4 minutes. The PASSkey(R) decoder module will continue this process even if a key with the correct pellet is used to turn the ignition back on. The timer is restarted by the ignition switch voltage at terminal A1 when the ignition switch is turned to RUN.

Once the timer has completed its 2 to 4 minute cycle with the ignition off, the PASSkey(R) decoder module and timer are reset. A key having the correct code can then be used to start the engine.

The security indicator is controlled directly by the PASSkey(R) decoder module. If there is a PASSkey(R) failure this indicator will be grounded by the PASSkey(R) decoder module with the ignition in RUN, BULB TEST, or START. When the ignition switch is first placed in RUN, BULB TEST, or START the indicator lights for about 2 seconds as a bulb check.