• | 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 |
---|---|---|---|---|
Flash to Pass Switch Signal | 1 | 2 | -- | -- |
Turn Signal/Multifunction Switch Ground | -- | 2 | -- | -- |
1. High beam headlamps always on with low beams 2. Flash to pass inoperative |
The flash to pass switch signal is referenced from battery voltage by the BCM. When the flash to pass switch is activated, the switch signal circuit is closed to ground and the signal circuit voltage goes low, indicating to the BCM the switch is active.
Headlights/Daytime Running Lights (DRL) Schematics
Exterior Lighting Systems Description and Operation
Control Module References for Scan Tool Information
Ignition ON, pull and release the flash to pass switch. The high beam headlamps should flash on and off.
⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. |
⇒ | If not the specified value, test the signal circuit terminal X2 B for a short to ground. If the circuit tests normal, replace the BCM. |
⇒ | If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for BCM replacement, programming, and setup |