• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
• | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
• | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
---|---|---|---|---|
Headlamp Low Beam Relay Control | 2 | 1 | B2575 00 | -- |
1. Headlamps Inoperative - Low Beams 2. Headlamps Always On - Low Beams |
The low beam headlamps are controlled by the body control module (BCM). The BCM grounds the headlamp low beam relay control circuit in order to energize the HID/LO BEAM relay coil. The HID/LO BEAM relay then sends voltage to the low beam headlamps.
• | The headlamps are commanded ON. |
• | The headlamp dimmer switch must be in the low beam position. |
The headlamp low beam relay control circuit is shorted to voltage.
The BCM turns off the headlamp low beam relay control for the remainder of the ignition cycle.
• | The conditions for setting the DTC are no longer present. |
• | A history DTC clears after 100 malfunction-free ignition cycles. |
Headlights/Daytime Running Lights (DRL) Schematics
Exterior Lighting Systems Description and Operation
Control Module References for scan tool information
Ignition ON, command the Low Beam ON with a scan tool. The Low Beam Relay Command parameter should display On and the low beam headlamps should illuminate.
⇒ | If the test lamp illuminates, test the control circuit for a short to voltage. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for BCM replacement, setup, and programming |