Headlamps Flash to Pass Inoperative

Headlamps Flash to Pass Inoperative

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview) provides an overview of each diagnostic category.

Circuit/System Description

The flash to pass switch simultaneously activates the headlamps on signal and the high beam signal inputs to the body control module (BCM). The BCM monitors the signal circuit voltage and when the flash to pass switch is activated the switch contacts close the headlamps on and high beam signal circuits to ground.

Reference Information
Schematic Reference

Headlights/Daytime Running Lights (DRL) Schematics (Headlights/Daytime Running Lights (DRL) Diagrams)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

Exterior Lighting Systems Description and Operation (Exterior Lighting Systems Description and Operation)
Electrical Information Reference

* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)

Scan Tool Reference

Control Module References (Programming and Relearning) for scan tool information

Circuit/System Verification

Ignition ON, observe the scan tool headlamp on switch and high beam select switch parameters while operating the flash to pass switch on and off. The readings should change between active and inactive.

Circuit/System Testing

1. Ignition OFF, disconnect the inline harness connector X204.
2. Test for less than 5 ohms between the ground circuit terminal B10 and ground.

• If greater than the specified range, test the ground circuit for an open/high resistance.

3. Ignition ON, verify the scan tool headlamp on switch parameter is inactive.

• If not the specified value, test the signal circuit terminal A10 for a short to ground. If the circuit tests normal, replace the BCM.

4. Verify the scan tool high beam select switch parameter is inactive.

• If not the specified value, test the signal circuit terminal A11 for a short to ground. If the circuit tests normal, replace the BCM.

5. Install a 3A fused jumper wire between the signal circuit terminal A10 and the ground circuit terminal B10. Verify the scan tool headlamp on switch parameter is active.

• 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.

6. Install a 3A fused jumper wire between the signal circuit terminal A11 and the ground circuit terminal B10. Verify the scan tool high beam select switch parameter is active.

• 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.

7. If all circuits test normal, test or replace the turn signal/multifunction switch.

Component Testing

Flash to Pass Switch Test
1. Ignition OFF, disconnect the inline harness connector X204.
2. Test for infinite resistance between the signal terminal A10 and the low reference terminal B10.

• If not the specified value, replace the turn signal/multifunction switch.

3. Test for infinite resistance between the signal terminal A11 and the low reference terminal B10.

• If not the specified value, replace the turn signal/multifunction switch.

4. Test for less than 5 ohms between the signal terminal A10 and the low reference terminal B10 while activating the flash to pass switch.

• If greater than the specified range, replace the turn signal/multifunction switch.

5. Test for less than 5 ohms between the signal terminal A11 and the low reference terminal B10 while activating the flash to pass switch.

• If greater than the specified range, replace the turn signal/multifunction switch.

Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

* Turn Signal Multifunction Switch Replacement (Turn Signal Multifunction Switch Replacement)
* Control Module References (Programming and Relearning) for BCM replacement, setup, and programming