Headlight (USA)

Exterior Lights

How the Headlights Circuit Works (USA)

High and Low Beams

The headlight relays receive battery voltage at all times from the driver's multiplex control unit. When you turn the headlight switch to the HEAD position with the dimmer switch in LOW, ground is applied through the GRN wire to the coils of the headlight relays. The relays are then energized, applying battery voltage to the left and right high and low beam headlight filaments through fuses 43 and 45 (in the under-hood fuse/relay box). The low beam bulbs come on because they are individually grounded by G301 and G201. With the low beams already on, pulling the dimmer switch to HIGH energizes the dimmer relay. When energized, the dimmer relay provides a path to ground for the high beam bulbs and the high beam indicator.

Flash-to-Pass

When you hold the flash-to-pass switch in the ON position, ground is applied through the GRN wire to the coils of the headlight relays. The relays are then energized, applying battery voltage to the left and right high and low beam headlight filaments through fuses 43 and 45 (in the under-hood fuse/relay box). The low beam bulbs come on because they are individually grounded by G301 and G201. With the flash-to-pass switch in ON, ground is provided to the dimmer relay coil. The dimmer relay is then energized, which provides a path to ground for the high beam bulbs and the high beam indicator.

Auto-off Lights Function (EX, SE, EX-L)

The headlight relays are controlled by the driver's multiplex control unit. If you leave the headlight switch in the HEAD position and exit the vehicle, the control unit will automatically turn the exterior lights off within 15 seconds after you close the doors. When you unlock or open the driver's door, the control unit automatically turns the lights back on.