General Description

- The Daytime Running Lamp (DRL) system consists of the following components which are integral to the DRL module:
- DRL module
- DRL sensor
- The DRL system is designed to automatically operate certain exterior lamps, depending on outside light conditions, whenever the ignition switch is in the RUN position.
- The DRL system operates in both a DAY or a NIGHT mode. In the DAY mode, the turn signal lamps are lit at full brilliance (non flashing). If the system is in the DAY mode and the turn signal switch is on, the turn signal lamps will flash normally.
In the NIGHT mode the front park/turn signal/sidemarker lamps and the taillamps are lit at full brilliance.
- The signal from the DRL sensor determines the DAY and the NIGHT modes. The DRL sensor is a photodiode element, which reacts to changes in light intensity. The DRL module monitors the signal from the DRL sensor and determines whether the system should operate in the DAY or the NIGHT mode.
- When the DRL module is in the DAY mode, the DRL module supplies voltage to the turn signal lamps (non flashing). When the DRL module is in the DAY mode and the turn signal switch is on, the DRL module will relay the hazard flasher voltage to the corresponding turn signal lamps and they will flash. At nightfall, as light intensity decreases, the DRL sensor signal changes.
In response to this change, the DRL module will change from DAY to NIGHT mode as a switching point is crossed.
- When NIGHT mode is initiated, the DRL applies voltage to the front park/turn signal/sidemarker lamps and the tail lamps. These lamps operate at full brilliance under these conditions.
- If the parking brake is applied before the ignition switch is turned from OFF to RUN, the DRL operation is canceled. As long as the brake is engaged, this function allows the driver to start the engine and keep the headlamps or turn signal lamps OFF. The DRL system operation resumes as soon as the parking brake is released. This deactivation feature only functions when the parking brake is applied before the ignition switch is turned to RUN. If the parking brake is applied after the ignition switch is turned to RUN, the DRL system operation will not be affected.
For DRL system wiring information and electrical diagnosis, Refer to Headlights Schematics (Domestic) or Headlights Schematics (Export) or Headlights Schematics (Export w/DRL).