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 on inputs from the hazard switch. With the hazard switch closed, a ground path is provided on the hazards switch signal circuit, indicating a hazard lamp request. When this request is seen, the BCM will pulse the turn signal lamp supply voltage circuits, illuminating the turn signal lamps.
Reference Information
Schematic Reference
Exterior Lights Schematics (Exterior Lights Schematics)
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, command the listed turn signal lamps ON and OFF with a scan tool. The lamps should turn ON and OFF between the commanded states.
* LF Turn Signal
* RF Turn Signal
* LR Turn Signal
* RR Turn Signal
• If the lamps do not turn ON and OFF, refer to Turn Signal Lamps and/or Indicators Malfunction (Turn Signal Lamps and/or Indicators Malfunction).
2. Observe the scan tool Hazard Lamp Switch parameter while cycling the hazard switch ON and OFF. The parameter should change between Active and Inactive.
• If the parameter does not cycle between the specified values, refer to Hazard Switch Malfunction.
3. Press and release the hazard switch. All applicable lamps should flash ON and OFF.
• If one or more of the lamps flash ON and OFF, refer to Turn Signal Lamps and/or Indicators Malfunction (Turn Signal Lamps and/or Indicators Malfunction)
• If none of the lamps flash ON and OFF, refer to Hazard Switch Malfunction.
Circuit/System Testing
Hazard Switch Malfunction
1. Ignition OFF, disconnect the X1 harness connector at the turn signal/multifunction switch.
2. Test for less than 5 ohms between the ground circuit terminal C and ground.
• If greater than the specified range, test the ground circuit for an open/high resistance.
3. Test for less than 5 ohms between the ground circuit terminal F and ground.
• If greater than the specified range, test the ground circuit for an open/high resistance.
4. Ignition ON, verify the scan tool Hazard Lamp Switch parameter is Inactive.
• If not the specified value, test the signal circuit terminal G 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 G and ground. Verify the scan tool Hazard Lamp Switch parameter is Active.
• 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.
6. If all circuits test normal, 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