Aviator 2WD V8-4.6L DOHC (2003)
Daytime Running Lamp Relay: Description and Operation
EXTERIOR LIGHTING
The headlamp switch supplies voltage to the headlamps (relays if equipped with high intensity discharge headlamps), parking lamps and the autolamp
system when demanded. If equipped with HID headlamps, the relays then provide power to the HID ballasts. The ballasts provide the necessary voltage
to illuminate the HID bulbs.
The headlamp switch also provides power to the parking, rear and license lamps.
The autolamp system, controlled by the vehicle security module, supplies voltage to the same circuits used by the headlamp switch to power the exterior
lamps when low light conditions are detected.
The autolamp system provides light sensitive automatic on/off control of the exterior lamps normally controlled by the headlamp switch. The autolamp
system keeps the exterior lamps on for a pre-selected period of time after the ignition switch is turned off. The pre-selected time lapse is adjustable up to
approximately three minutes.
The standard headlamp system is a quad-beam pattern system. It consists of a low and high beam, with two replaceable bulbs. The headlamp assembly
has the park/turn lamps integrated into the headlamp assembly.
The fog lamp switch is integral to the headlamp switch.
The daytime running lamps system operates the high-beam headlamps at a reduced intensity. The DRL module supplies pulse width modulated (PWM)
voltage, 80% of battery voltage, to the high-beam headlamps when the following conditions are met:
-
the multifunction switch is in the neutral position
-
the parking brake control is released
-
the headlamp switch is not in the headlamps ON position
-
the ignition switch is in the RUN position
-
the autolamps feature has not activated the headlights
The DRL module remains enabled when the flash-to-pass feature is requested.
