Hazard Lamps Inoperative With VTSS

*HAZARD LAMPS INOPERATIVE WITH VTSS

For a complete wiring diagram refer to Diagrams/Electrical





Diagnostic Test

1. CHECK FOR DTCs IN THE BCM

Turn the ignition on.

With the scan tool, read BCM DTCs.

Does the scan tool display any DTCs?

Yes

- Diagnose and repair the DTC(s).
- Perform VTSS VERIFICATION TEST - 1A. VTSS Verification Test

No

- Go To 2

2. CHECK HAZARD LAMP OPERATION USING THE HAZARD SWITCH

Operate the Hazard Lamps with the Hazard Switch.

Do the hazard lamps operate?

Yes

- Go To 3

No

- Diagnose and repair the hazard lamps.
- Perform VTSS VERIFICATION TEST - 1A. VTSS Verification Test

3. ACTUATE THE HAZARD LAMPS WITH THE SCAN TOOL

Turn the Hazard Switch off.

With the scan tool in BCM, actuate the Hazard Lamps.

Do the Hazard Lamps operate?

Yes

- Replace and program the BCM.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test

No

- Go To 4

4. CHECK (L91) HAZARD LAMP CONTROL CIRCUIT FUNCTION

Using the scan tool, turn the Hazard Lamp actuator off.

Turn the ignition off.

Disconnect the BCM C1 harness connector.

Connect a jumper wire between the (L91) Hazard Lamp Control circuit and ground.

Do the Hazard Lamps operate?

Yes

- Replace and program the BCM.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test

No

- Go To 5

5. CHECK (L91) HAZARD LAMP CONTROL CIRCUIT FOR AN OPEN

Disconnect the Hazard Switch harness connector.

Measure the resistance of the (L91) Hazard Lamp Control circuit between the BCM C1 harness connector and the Hazard Switch harness connector.

Is the resistance below 5.0 ohms?

Yes

- Replace the Hazard Switch.
- Perform VTSS VERIFICATION TEST - 1A. VTSS Verification Test

No

- Repair the (L91) Hazard Lamp Control circuit for an open.
- Perform VTSS VERIFICATION TEST - 1A. VTSS Verification Test