With Fog Lights (SE)

The Light Control Module automatically turns on the Headlights and Exterior Lights when it is dark outside, The Module keeps the lights on for a selected amount of time after the Ignition Switch has been turned to OFF.
When the Ignition Switch is in RUN and the Light Control Module senses darkness, the Module's Headlight Control closes, applying voltage to the Headlights through the Headlight Dimmer Switch. The Module's Exterior Lights Control also closes, applying voltage to the Front and Rear Marker Lights, Park Lights, License Plate Lamps and Tail Lights.

On/Off Input

When the Twilight Sentinel Control is placed in the ON position, the Module automatically turns on the Headlights and Exterior Lights when it gets dark. On T61 equipped vehicles, the Daytime Running Lights operation is not affected by the Twilight Sentinel Control's position.

Photocell Input

The Twilight Sentinel/Daytime Running Lights Photocell is a variable resistor. Its resistance decreases as outside light intensity increases. The Light Control Module measures the voltage across the Photocell to determine whether it is day or night.

Delay Input

When the Ignition Switch is turned to OFF, the Module keeps the lights on at night for at least five seconds and not more than 4 1/2 minutes. The resistance of the rheostat in the Twilight Sentinel Control sets the delay period.

Daytime Running Lights

On vehicles equipped with Daytime Running Lights, the Light Control Module has an additional function: it turns on the Lo Beam Headlights at a reduced brilliance in daylight conditions.

Park Input

The Daytime Running Lights mode is disabled when the battery voltage is applied to the Module's Park Input (terminal C2/B8). This occurs anytime the gear selector lever is placed in park.

Fog Lights

With the Head/Park Light Switch in HEAD or PARK and the Fog Light Switch ON, voltage is applied to the Fog Light Relay Coil. The Coil is grounded by the Light Control Module. With the relay energized, its contacts close, applying voltage to the Fog Lights. If the headlights are switched to HI Beam, voltage is applied to the Light Control Module's HI Beams On Input, terminal C2/B5, causing the Light Control Module's Fog Light Relay Control, terminal C2/A1, to open. This removes the ground from the Fog Light Relay Coil, de-energizing the relay. The relay contacts open, removing voltage from the Fog Lights. The Fog Lights go out.