Hazard Lamps Malfunction

Hazard Lamps Malfunction

Diagnostic Instructions

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

Circuit/System Description

The body control module (BCM) is responsible for controlling the turn signals and hazard lamps. When the turn signal switch is placed in either the left turn or right turn position, the BCM receives a signal from the turn signal switch. The BCM then sends an on-off voltage signal to either the left or right turn signals and their instrument panel cluster (IPC) indicator. When the hazard switch is pressed, the BCM receives a signal from the hazard switch. The BCM then will send an on-off voltage signal to all the turn signal lamps. All the turn signal lamps will flash including both IPC turn signal indicators.

Circuit/System Verification

1. Ignition ON, turn signal switch OFF. The turn signal lamps should not illuminate.

^ If the either turn signal lamp illuminates, refer to Turn Signal Always On.

2. Command the left and right turn signals ON and OFF with a scan tool. The turn signals and indicators should illuminate and flash when commanded ON.

^ If the turn signals do not illuminate and flash when commanded ON, refer to Turn Signals Inoperative From BCM.
^ If the turn signal indicators do not illuminate and flash, refer to Turn Signal Indicators Inoperative.

3. Hazard switch ON, the turn signal lamps should illuminate and flash.

^ If the turn signals do not illuminate and flash, refer to Hazard Lamps Inoperative.

4. Refer to Turn Signals Inoperative From Switch.

Circuit/System Testing

Turn Signals Always On
1. Ignition OFF, disconnect the X2 harness connector at the turn signal/multifunction switch.
2. Ignition ON, the turn signals should not be flashing.

^ If the turn signals are flashing, test the appropriate signal circuit for a short to ground:

* Left turn signal - terminal G. If the circuit tests normal, replace the BCM.
* Right turn signal - terminal H. If the circuit tests normal, replace the BCM.

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

Turn Signals Inoperative From BCM
1. Ignition OFF, disconnect the harness connector at the inoperative turn signal.
2. Connect a test lamp between the ground circuit terminal C and B+. The test lamp should illuminate.

^ If the test lamp does not illuminate, test the ground circuit terminal C for a short to voltage or an open/high resistance.

3. Test the supply voltage circuit terminal A for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.

Turn Signal Indicators Inoperative
1. Command the instrument panel Display Test ON with a scan tool. The turn signal indicators should illuminate.

^ If the turn signal indicators do not illuminate, replace the instrument panel cluster.

2. If all circuits test normal, replace the BCM.

Turn Signals Inoperative From Switch
1. Ignition OFF, disconnect the X2 harness connector at the turn signal/multifunction switch.
2. Verify that a test lamp illuminates between the ground circuit terminal B and B+.

^ If the test lamp does not illuminate, test the ground circuit for a short to voltage or an open/high resistance.

3. Install a 3A fused jumper wire between the signal circuit of the inoperative turn signal and ground.

* Left turn signal - terminal G.
* Right turn signal - terminal H.

4. Ignition ON, the turn signal should illuminate and flash.

^ If the turn signal does not illuminate and flash, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM.

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

Hazard Lamps Inoperative
1. Ignition OFF, disconnect the harness connector at the hazard switch.
2. Verify that a test lamp illuminates between the ground circuit terminal A and B+.

^ If the test lamp does not illuminate, test the ground circuit terminal A for a short to voltage or an open/high resistance.

3. Install a 3A fused jumper wire between the signal circuit terminal D and ground. The turn signals should illuminate and flash.

^ If the turn signals do not illuminate and flash, test the signal circuit terminal D for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM.

4. If all circuits test normal, replace the hazard switch.

Repair Instructions

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

* Turn Signal Multifunction Switch Replacement
* Instrument Cluster Replacement
* Hazard Warning Switch Replacement