Diagnostic Instructions
| • | 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. |
Diagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
Flash to Pass Switch Signal | 1 | 2 | -- | -- |
Headlamp Dimmer Switch Ground | -- | 2 | -- | -- |
1. High beam headlamps always on with low beams 2. Flash to pass inoperative | ||||
Circuit/System Description
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.
Reference Information
Schematic Reference
Headlights/Daytime Running Lights (DRL) Schematics
Connector End View Reference
Description and Operation
Exterior Lighting Systems Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for Scan Tool Information
Circuit/System Verification
Ignition ON, pull and release the flash to pass switch. The high beam headlamps should flash on and off.
Circuit/System Testing
- Ignition OFF, disconnect the harness connector X2 at the turn signal/multifunction switch.
- Test for less than 1 ohm of resistance between the ground circuit terminal D X2 and ground.
- Ignition ON, verify the scan tool flash to pass switch parameter is off.
- Install a 3A fused jumper wire between the signal circuit terminal E X2 and the ground circuit terminal D X2. Verify the scan tool flash to pass switch parameter is on.
- If all circuits test normal, test or replace the turn signal/multifunction switch.
| ⇒ | 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 E X2 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. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for BCM replacement, programming, and setup |
