Hazard Lamps Malfunction

Hazard Lamps Malfunction

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.

* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Circuit/System Description

The hazard flashers may be activated in any power mode. The hazard switch is integrated into the radio/HVAC control assembly. When the hazard switch is placed in the ON position, the radio communicates via serial data with the body control module (BCM) requesting the hazard lamps be activated. The BCM supplies battery voltage to all four turn signal lamps in an ON and OFF duty cycle. When the hazard switch is activated, the BCM sends a serial data message to the instrument panel cluster (IPC) requesting both turn signal indicators to be cycled ON and OFF.

Reference Information

Schematic Reference

Exterior Lights Schematics Exterior Lights Schematics.

Connector End View Reference

Component Connector End Views Fuel Pump and Level Sensor Assembly.

Description and Operation

Exterior Lighting Systems Description and Operation Exterior Lighting Systems.

Electrical Information Reference

* Circuit Testing Circuit Testing.

* Connector Repairs Connector Repairs.

* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections.

* Wiring Repairs Wiring Repairs.

Scan Tool Reference

Control Module References Control Module References for scan tool information.

Circuit/System Verification

Ignition ON, observe the scan tool Hazards parameter while pressing and depressing the hazard switch. The parameter should change between Active and Inactive.

If the parameter changes as the switch is activated, replace the K9 body control module.

If the parameter does not change as the switch is activated, replace the A11 radio control assembly.

Repair Instructions

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

* Radio Control Assembly Replacement Radio Control Assembly Replacement

* Control Module References Control Module References for BCM replacement, setup, and programming