Interior Lighting Systems
WARNING: This page is about a different car, the 2003 Lincoln Navigator and 2003 Ford Expedition. However, it is still accessible from the selected car via links, so may be relevant.
The instrument cluster grounds the battery saver relay and supplies the power for courtesy lamps when any door ajar switch is opened, or the interior lamp (headlamp) switch is closed. The instrument cluster then supplies voltage to the interior lamp circuit. Vehicle speed must be less than 24 kph (15 mph) for the instrument cluster module to keep courtesy lamps on. The interior lamps will remain illuminated for up to 25 seconds after all doors are closed unless the instrument cluster module receives an input from any of the following:
- voltage from the ignition switch
- a vehicle speed signal
- input from the keyless entry keypad through the vehicle security module
- input from the remote keyless entry transmitter lock or panic switch through the vehicle security module