With Daytime Running Lights (DRL)

Depending on the outside light conditions, the Daytime Running Lights (DRL) Module automatically turns on either the Headlights or the Headlights and Front/Tail Lights. The gear selector must be out out "PARK/NEUTRAL" for the DRL Module to operate. The DRL Module operates in two modes:

^ In the Day Mode, the LO Beam and HI Beam Headlights are lit at a reduced brilliance.
^ In the Night Mode, the LO or HI Beam Headlights are lit at full brilliance and the Front Marker, Park and Tail Lights are lit.

When the Photoresistor senses high ambient light, the DRL Module operates in Day Mode. The Day Mode contacts close, applying voltage to LO Beam and HI Beam Headlights through CKT 593. The LO Beam and HI Beam Headlights are lit at a reduced brilliance.

When the Photoresistor senses low ambient light, the DRL Module operates in Night Mode. The Night Mode contacts close, applying voltage to the LO or HI Beam Headlights and other Exterior Lights through the same circuit path as when the Headlight Switch is in "HEAD."

PHOTORESISTOR INPUT

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

PARK/NEUTRAL INPUT

The DRL Module has an input from the Electronic PRNDL Control Module circuit. When the gear selector is in "PARK/NEUTRAL," ground is applied to the DRL Module DRL disable input. The DRL Module then will not operate any Headlights or Exterior Lights (in Day or Night Modes.) This allows the operator to start the car and keep the Headlights off as long as gear selector is in Park/Neutral. Once the DRL Module turns the Daytime Running Lights on, putting the gear selector back into "PARK" or "NEUTRAL" will not turn the Daytime Running lights off.