Headlamp: Description and Operation

The HEADLAMPS receive battery voltage through the RIGHT HEADLAMP and LEFT HEADLAMP Fuses at all times. When the Headlamp Switch is in the HEAD position, a ground is provided through the DAYTIME RUNNING LAMPS (DRL) CONTROL MODULE and the Headlamp/Dimmer Switch at G201. When the Headlamp Switch is in the OFF or PARK position, a ground is provided through the DRL CONTROL MODULE and the DRL RESISTOR at G104, provided that all conditions for Daytime Running Lamps operation are met. High and low-beam selection is provided by grounding the high and low-beam filaments separately. The high-beam filaments are grounded through the Headlamp/Dimmer Switch at G201. The low-beam filaments are grounded through the DRL CONTROL MODULE and the Headlamp/Dimmer Switch at G201.

The DRL system operates the low-beam HEADLAMPS at 80% intensity. DRL system operation is initiated when the DRL CONTROL MODULE senses all of the following:
^ A charge input signal from the GENERATOR at terminal 5, indicating an "engine running" condition.
^ No ground signal from the PARKING BRAKE SWITCH at terminal 4, indicating that the parking brake is not engaged.
^ A "Lights OFF" signal at terminal 11, indicating the Headlamp/Dimmer Switch is in either the "OFF" or PARK position.

The DRL CONTROL MODULE receives battery voltage for system operation at terminal 7 from the IG-COIL METER Fuse whenever the Ignition Switch is in the "ON" or "START" position. The DRL CONTROL MODULE is permanently grounded at G200 through terminal 8.