Diagnostic Aids
Important: The stop lamps will not illuminate unless the ignition is in the ON position. For more detailed information concerning stop lamp operation, refer to Exterior Lighting Systems Description and Operation .
Thoroughly inspect the wiring and connectors. An incomplete inspection of the wiring and connectors may result in misdiagnosis causing part replacement with the reappearance of the malfunction. If an intermittent malfunction exists, refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Exterior Lights Schematics Connector End View Reference: Master Electrical Component List in Wiring Systems | |||
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
2 |
Did the CHMSL operate properly? | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems | Go to Step 3 |
3 | Are DTCs P0719 or P0724 set as current? | Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC Information | Go to Step 4 |
4 |
Does the test lamp illuminate? | Go to Step 5 | Go to Step 11 |
5 |
Does the test lamp illuminate? | Go to Step 6 | Go to Step 12 |
6 |
Does the CHMSL illuminate? | Go to Step 10 | Go to Step 7 |
7 |
Does the test lamp illuminate? | Go to Step 9 | Go to Step 8 |
8 | Test the CHMSL supply voltage circuit for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 17 | Go to Step 13 |
9 | Inspect for poor connections at the CHMSL harness connector. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 17 | Go to Step 15 |
10 | Inspect for poor connections at the stop lamp relay. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 17 | Go to Step 14 |
11 | Inspect for poor connections at the harness connector of the body control module (BCM). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 17 | Go to Step 16 |
12 | Locate and repair an open or high resistance in the stop lamp relay switch side supply voltage circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 17 | -- |
13 | Locate and repair an open or high resistance in the CHMSL ground circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 17 | -- |
14 | Replace the stop lamp relay. Refer to Relay Replacement in Wiring Systems. Did you complete the replacement? | Go to Step 17 | -- |
15 | Replace the CHMSL. Refer to High Mount Stop Lamp Replacement . Did you complete the replacement? | Go to Step 17 | -- |
16 | Replace the BCM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming. Did you complete the replacement? | Go to Step 17 | -- |
17 | Operate the system in order to verify the repair. Did you correct the condition? | System OK | Go to Step 2 |
