Lighting and Horns: Description and Operation

Exterior Lights System Description

Headlights System Description

The headlight system is composed of the MICU, the relay control module, the taillight relay, the headlight and dimmer/flash-to-pass switches (inside the combination light switch), the headlights, and the high beam indicator.

The taillight relay controls each side of the front parking/side marker light, taillights, rear side marker light, and license plate lights. The headlights, daytime running lights, and the turn signal/hazard lights are controlled by the MICU. The back-up lights are controlled by the reverse relay.

Low Beams

When you move the headlight switch to the headlight ON position and the dimmer/flash-to-pass switch to the low position, a ground signal is supplied to terminal No. 15 of driver's under-dash fuse/relay box connector P (24P). The MICU then energizes the low beams control circuit, supplying battery voltage to the low beams of the left headlights, turning them on.

NOTE: If there is a B-CAN communication failure, the headlight back-up circuit commands the right low beam to come on when the ignition is on and the headlight switch is in the ON position. The right high beam does not come on if there is a B-CAN system failure.

High Beams

When you move the headlight switch to the headlight ON position and the dimmer/flash-to-pass switch to the high position, ground signals are supplied to terminals No. 19 and No. 21 of driver's under-dash fuse/relay box (MICU) connector P (24P). The MICU then energizes each side of the high beam headlight control circuits, supplying battery voltage to the high beam headlights, turning them on.

Flash-to-Pass

When you pull the dimmer/flash-to-pass switch to the passing position, a ground signal is supplied to terminal No. 20 of the driver's under-dash fuse/relay box (MICU) connector P (24P). The MICU then energizes the high beam control circuits for as long as the switch is held, supplying battery voltage to the high beam headlights, turning them on.

Day Time Running Lights System Description

The daytime running lights system includes the relay control module, the left and right high beam headlights, the parking brake switch, and the DRL indication on the multi-information display (MID) (With multi-information display) or the DRL indicator (Without multi-information display). The daytime running lights operate with the ignition switch turned to ON (II), the headlights off (headlight switch OFF or in the parking position), and the parking brake released.

When the daytime running lights are on, the relay control module turns each relative daytime running lights control circuit on and off (duty cycle), which provides a reduced voltage (approximately 6-8 volts) to the daytime running lights (via the No. B20 and B24 fuses in the driver's under-dash fuse/relay box); the daytime running lights come on with reduced brightness. The relay control module also sends signals to the gauge control module, and the DRL indication is indicated by the lights-on indicator.

NOTE:

- The daytime running lights are disabled when the ignition switch is turned to LOCK (0). To keep the daytime running lights from coming on, apply the parking brake switch while the ignition switch is in LOCK (0) position. When you then turn the ignition switch back to ON (II) the daytime running lights will not come on until the parking brake is released.
- The headlights revert to normal operation when you turn them on with the headlight switch.