With Daytime Running Lights (DRL)

CIRCUIT OPERATION

The Daytime Running Lights (DRL) Module is designed to automatically operate Exterior Lights depending on outside light conditions. The DRL Module operates in two modes. In the Day Mode, the LOW Beam Headlights are lit at reduced brilliance. In the Night Mode, the LOW Beam Headlights are lit at full brilliance and the Front Marker, Park and Tail Lights are lit.

When the DRL Module is in the Day Mode, the Day Mode contacts close, applying voltage to the Diode Assembly and the LOW Beam Headlights. The Diode Assembly reduces the voltage applied to the Headlights, thus reducing the brilliance of the Headlights.

When the Ambient Light Sensor senses darkness, the DRL Module operates in the Night Mode. The Night Mode contacts close, applying voltage to the Headlights and other Exterior Lights through the same circuit path as when the Headlight Switch is in "HEAD."

If the Engine should stall with the DRL Module in the Night Mode, the DRL Module will turn off the Headlights and leave the Marker, Park and Tail Lights lit while the Engine is being cranked. The Headlight Switch operates as usual.

AMBIENT LIGHT SENSOR
The Ambient Sensor is a light sensitive variable resistor. Its resistance decreases as outside light intensity increases. The DRL Module measures the voltage drop across the Ambient Light Sensor and determines whether it should operate in the Day Mode or Night Mode.

PARK BRAKE INPUT
If the Park Brake is applied before the Ignition Switch is turned to "RUN," the DRL Module will not operate any Headlights or Exterior Lights. This allows the operator to start the vehicle and keep the Headlights off, as long as the Park Brake is applied. When the Park Brake is released with the Ignition Switch in "RUN," the DRL Module will activate the Headlights.

This feature will only function when the Park Brake is applied before the Ignition Switch is turned to "RUN." If the Park Brake is applied after the Ignition Switch is turned to "RUN," the Headlights will not turn off.

"HI BEAM ON" INPUT

4 Door - The DRL Module will turn the LOW Beam Lamps "OFF" if it senses battery voltage at the "HI BEAM ON" input. This is to prevent the LOW Beam and HI Beam Headlights from operating at the same time. The "HI BEAM ON" input will sense battery voltage when the "FLASH-TO-PASS" feature is operated.

2 Door - The HI Beam on input operates similar to the Sedan except that the LOW Beam Headlights remain on with the HI Beam Headlights. This is due to the Mini-Quad Relay which is energized any time the HI Beam Headlights are "ON."

FOG LAMPS
When the Light Switch is in "PARK" or "HEAD" or when the DRL Module is operating in the Night Mode, voltage is applied to the Fog Lamp Switch Assembly. When the Fog Lamp Switch is turned "ON," voltage is applied to the Fog Lamp Relay. With the Headlight Dimmer Switch in "LO," ground is provided for the Fog Lamp Relay through the HI Beam filaments and the Fog Lamps turn "ON." When the Headlight Dimmer Switch is moved to "HI," battery voltage is at both sides of the Fog Lamp Relay coil and the Fog Lamps go "OFF."