Circuit Description

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The DRL 10 A fuse in the engine wiring harness junction block supplies battery positive voltage to the Daytime Running Lamp (DRL) relay switch contacts. The IGNE 10 A fuse in the engine wiring harness junction block supplies ignition positive voltage to the DRL relay coil. When the BCM energizes the DRL relay in daylight conditions, the current flow is to both DRL lamps and to ground G100.

The Body Control Module (BCM) monitors the ambient light sensor signal circuit of the ambient light sensor in order to determine if the Daytime Running Lights (DRL) or the Auto Headlights (AHL) should be turned ON in the AUTO mode. When the BCM senses the ambient light sensor voltage between 1.7-4.7 volts (light state) the DRL will be commanded ON. When the BCM senses the ambient light sensor voltage between 0.2 1.0 volts (dark state) the AHL will be commanded ON.