For 1990-2009 cars

Step | Action | Yes | No
--- | --- | --- | ---
Schematic Reference: Exterior Lights Schematics . Connector End View Reference: Component Connector End Views .
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | Go to Diagnostic System Check - Vehicle .
2 | Depress the brake pedal. Does the system operate normally? | Go to Testing for Electrical Intermittents . | Go to Step 3
3 | Disconnect the stop lamp switch. Do the stop lamps/centre high mounted stop lamp (CHMSL) remain illuminated? | Go to Step 4 | Go to Step 6
4 | Disconnect the associated body control module (BCM) connector. Do the stop lamps remain illuminated? | Repair the short to voltage in the stop lamp supply voltage circuit. Refer to Wiring Repairs . | Go to Step 5
5 | Disconnect the BCM connector. Does the CHMSL remain illuminated? | Repair the short to voltage in the CHMSL supply voltage circuit. Refer to Wiring Repairs . | Repair the short to voltage in the stop lamp switch signal circuit. Refer to Wiring Repairs .
6 | Inspect for poor connections at the harness connector of the stop lamp switch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition? | System OK | Replace the stop lamp switch. Refer to Stop Lamp Switch Replacement .