Hazard Lamps Malfunction

Hazard Lamps Malfunction

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.

Diagnostic Fault Information





Circuit/System Description

The Body Control Module (BCM) controls the hazard lamps based an input from the hazard lamp switch. When the hazard lamp switch is depressed, a ground signal is provided to the BCM on the hazard switch signal circuit. This indicates to the BCM that the hazard lamps are requested. The BCM will then activate the hazards lamps by pulsing the turn signal lamp supply voltage circuits.

Reference Information
Schematic Reference

Exterior Lights Schematics (Exterior Lights 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

1. Ignition ON, operate the left and right turn signals using the multifunction turn signal lever. Each of the turn signal lamps should pulse when commanded ON by the lever.

• If the turn signal lamps do not function as specified, refer to Turn Signal Lamps and/or Indicators Malfunction (Turn Signal Lamps and/or Indicators Malfunction).

2. Observe the scan tool Hazard Switch Signal parameter while cycling the hazard lamp switch ON and OFF. The parameter should change between On and Off.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the Driver Information Center (DIC).
2. Test for less than 10 ohms between the ground circuit terminal 4 and ground.

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

3. Ignition ON, verify the scan tool Hazard Switch Signal parameter is Off.

• If not the specified value, test the signal circuit terminal 2 for a short to ground. If the circuit tests normal, replace the BCM.

4. Install a 3A fused jumper wire between the signal circuit terminal 2 and ground. Verify the scan tool Hazard Switch Signal parameter is On.

• If not the specified value, test the signal circuit for a short to voltage or and open/high resistance. If the circuit tests normal, replace the BCM.

5. If all circuits test normal, test or replace the DIC.

Repair Instructions

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

* Driver Information Display Switch Replacement (Service and Repair)
* Control Module References (Programming and Relearning) for BCM replacement, setup, and programming