Daytime Running Lamps (DRL)

With the Ignition Switch in "ON" or "START", voltage is applied to the DRL Control Module through the GAUGE Fuse. A number of conditions must be met before the Daytime Running Lamps system will work properly: the parking brake must be disengaged, the DRL Control Module must not receive a ground signal from the Generator (a ground signal from the generator indicates that the generator is not charging the battery) and the Light Switch is either in the "OFF" or PARK position. When the parking brake is engaged, the Parking Brake Switch closes, providing a ground to the DRL Control Module, disabling DRL operation. This only happens when the car is first started: after disengaging the Parking Brake the first time, the DRL operation will continue even if the Parking Brake is re-engaged. When the Generator is not running, a switch in the Generator closes, providing a ground to the DRL Control Module, disabling DRL operation. When the Light Switch is in the HEAD position, a path to G200 through the Light Switch is provided to the DRL Control Module, disabling DRL operation.

When all these conditions are met, a path to ground is provided to the coil of DRL Relay 2. Voltage is applied through the closed contacts of DRL Relay 2 and the HEAD FUSE (LH-UPR) to the High Beam Lamp in the LH Headlamp. With no voltage applied to DRL Relay 3/4, the High Beam Lamp in the LH Headlamp has no direct path to ground. Since ground is provided at all times to the High Beam Lamp in the RH Headlamp and the High Beam Lamps are spliced together, the LH and RH High Beam Lamps are connected in series. With voltage applied to the High Beam Lamp in the LH Headlamp, and ground provided to the High Beam Lamp in the RH Headlamp through Junction Connector 2, the un-energized contacts of DRL Relay 3 (in DRL Relay 3/4 assembly) and Junction Block 1 to G104, the High Beam Lamps will light at half intensity.

The DRL Control Module will also provide a ground to the DRL Indicator when the DRL operation conditions are met. With voltage applied to the DRL Indicator through the GAUGE Fuse, and ground provided through the DRL Control Module, Junction Connector 3 and Junction Connector 1 to G200, the DRL Indicator will light.