Stop Lamps Always On

WARNING: This page is about a different car, the 2007 GMC Sierra and 2007 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.

Step	Action	Yes	No
Schematic Reference: Exterior Lights Schematics Connector End View Reference: Lighting Systems Connector End Views or Data Communication 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. Connect a fused jumper between the stop lamp switch harness terminals C and D. Do the brake lamps center high mount stop lamp (CHMSL) remain illuminated?	Go to Step 4	Go to Step 7
4	Disconnect the body control module (BCM) connector C 6. Do the brake lamps remain illuminated?	Go to Step 9	Go to Step 5
5	Disconnect the BCM connector C 5. Does the CHMSL remain illuminated?	Go to Step 10	Go to Step 6
6	Test the following circuits for an open or short to ground. Refer to Circuit Testing and Wiring Repairs . The brake pedal switch normally closed contact signal circuit The brake switch 12 volt reference circuit The battery positive voltage circuit to the BCM at connector C 4, terminal 4 Did you find and correct the condition?	Go to Step 13	Go to Step 8
7	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?	Go to Step 13	Go to Step 11
8	Inspect for poor connections at the harness connector of the BCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition?	Go to Step 13	Go to Step 12
9	Repair the short to voltage in the stop lamp supply voltage circuit. Refer to Wiring Repairs . Did you complete the repair?	Go to Step 13	-
10	Repair the short to voltage in the CHMSL supply voltage circuit. Refer to Wiring Repairs . Did you complete the repair?	Go to Step 13	-
11	Replace the stop lamp switch. Refer to Stop Lamp Switch Replacement (Non-Adjustable Pedal) or Stop Lamp Switch Replacement (Adjustable Pedal) . Did you complete the replacement?	Go to Step 13	-
12	Replace the BCM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement?	Go to Step 13	-
13	Operate the system in order to verify the repair. Did you correct the condition?	System OK	Go to Step 3