Normal Operation

WARNING: This page is about a different car, the 2006 Mercury Grand Marquis and 2006 Ford Crown Victoria. However, it is still accessible from the selected car via links, so may be relevant.

When the key is inserted into the ignition cylinder, the key-in-ignition switch (part of the ignition switch) closes circuit 158 (BK/PK) to the lighting control module (LCM), providing a voltage signal. The voltage input signals the instrument cluster that the key is inserted. If the instrument cluster detects that the ignition switch is in the OFF or ACC position, the key is inserted in the ignition cylinder, and the driver door is ajar, the key-in-ignition warning chime sounds.

The headlamp switch sends a signal to the lighting control module (LCM) through circuit 1032 (WH/BK) to indicate the parking lamps are on. The LCM monitors the driver door ajar switch and sounds a chime if the driver door is open, the parking lamps are on, and the ignition switch is not in the ON position.