Ambient Light Sensor: Description and Operation

The Headlamp Dimmer Sensor senses the headlights of oncoming cars. The Hi-Lo Beam Photocell Amplifier on the rear view mirror activates the Hi-Lo Beam Relay when oncoming headlights are sensed. The relay switches the headlamps to Lo Beams. When oncoming headlight are no longer sensed, the relay switches the headlamps back to hi beams.

Dimmer sensitivity is adjustable by the Hi-Lo Beam Range Control portion of the Auto Dimmer/Automatic Headlamp Control on the Instrument Panel. Rotating the control thumbwheel up increases the sensitivity (headlamps will dim at greater distance).

When the Multi-function Switch Dimmer Switch is puled partway toward the driver, the flash-to-pass is activated and the Hi Beams will flash.