The daytime running lamps (DRL) control module and the headlamp/dimmer switch control the headlamp. With the switch in the HEAD position and the dimmer switch in LO, ground is provided to the low beam filaments through the dimmer switch and the closed contacts of the headlamp relay 1 to G201. The LEFT HEADLAMP fuse and the RIGHT HEADLAMP fuse supply the voltage at all times. The low beam filaments will light when the voltage applies.
With the dimmer switch in the HI position, the high beam filaments in the headlamps ground through the dimmer switch, through the closed contacts of the headlamp relay 1 to G201. The LEFT HEADLAMP fuse and the RIGHT HEADLAMP fuse supply the voltage to the headlamps at all times. The high beam filaments will light when the voltage applies. The ground to the High Beam Indicator is the same as the high beam filaments. The LEFT HEADLAMP fuse applies the voltage to the high beam indicator at all times. The indicator will light when the voltage applies.
With the dimmer switch in the PASS position, the high beam filaments in the headlamps ground through the dimmer switch and headlamp relay 1 to G201. The LEFT HEADLAMP fuse and the RIGHT HEADLAMP fuse supply the voltage to the headlamps at all times. The high beam filaments will light. The ground to the high beam indicator is the same as the high beam filaments. The LEFT HEADLAMP fuse applies the voltage to the high beam indicator at all times. The indicator will light.
The ON or START position of the ignition switch applies voltage to the DRL control module through the IG-COIL METER Fuse. The DRL control module permanently grounds to G200. The following conditions are required before the DRL system will work properly:
| • | Disengage the parking brake |
| • | The DRL control module must not receive a ground signal from the generator. |
| A ground signal from the generator indicates the generator is not charging the battery. |
| • | The headlamp/dimmer switch is either in the OFF or in the PARK position. |
When the parking brake engages, the parking brake switch closes. The switch provides a ground to the DRL control module. The ground disables the DRL operation. When the generator is not running, a switch in the generator closes. The switch provides a ground to the DRL control module. The ground disables the DRL operation.
When all of the conditions for DRL operation are met, the DRL control module provides a ground for the low beam filaments in the headlamps through the DRL control module to G200. The LEFT HEADLAMP fuse and the RIGHT HEADLAMP fuse supply the voltage to the headlamps at all times. The low beam filaments will light at 80% intensity.
When all of the conditions for DRL operation are met, the DRL control module provides a ground for the DRL indicator. Voltage applies to the DRL indicator through the IG-COIL METER fuse. The voltage causes the DRL indicator to light.
