Diagnostic Test
- CHECK FOR AN ACTIVE DIAGNOSTIC TROUBLE CODE (DTC)
- Turn the ignition on.
- With the scan tool, read DTCs.
Does the scan tool display this DTC as active?
Yes
- Go To 2
No
- Test complete. The condition or conditions that originally set this DTC are not present at this time. Using the appropriate SYSTEM WIRING DIAGRAMS as a guide, check all related splices and connectors for signs of water intrusion, corrosion, pushed out or bent terminals and correct pin tension.
- CHECK THE SPEED CONTROL SWITCH
- Turn the ignition off.
- Disconnect the Speed Control Switch harness connector.
- Turn the ignition on.
- With the scan tool, read DTCs.
Does the scan tool display this DTC as active?
Yes
- Go To 3
No
- Replace the Speed Control Switch in accordance with the Service Information. Refer to SWITCH, SPEED CONTROL, REMOVAL .
- Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
- CHECK THE (V72) SPEED CONTROL SIGNAL 2 CIRCUIT FOR A SHORT TO VOLTAGE
- Disconnect the BCM C8 harness connector.
- Measure the voltage between ground and the (V72) Speed Control Signal 1 circuit at the BCM C8 harness connector.
Is there any voltage present?
Yes
- Repair the (V72) Speed Control Signal 1 circuit for a short to voltage.
- Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
No
- Go To 4
- CHECK THE (V72) SPEED CONTROL SIGNAL 2 CIRCUIT FOR AN OPEN
- Measure the resistance of the (V72) Speed Control Signal 2 circuit between the Speed Control Switch harness connector and the BCM C8 harness connector.
Is the resistance below 5.0 Ohms?
Yes
- Go To 5
No
- Repair the open in the (V72) Speed Control Signal 2 circuit.
- Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
- Measure the resistance of the (V72) Speed Control Signal 2 circuit between the Speed Control Switch harness connector and the BCM C8 harness connector.
- CHECK THE (V937) SPEED CONTROL SWITCH GROUND CIRCUIT FOR AN OPEN
- Measure the resistance of the (V937) Speed Control Switch Ground circuit between the Speed Control Switch harness connector and the BCM C8 harness connector.
Is the resistance below 5.0 Ohms?
Yes
- Replace Body Control Module (BCM) in accordance with the Service Information. Refer to MODULE, BODY CONTROL (BCM), REMOVAL .
- Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
No
- Repair the open in the (V937) Speed Control Switch Ground circuit.
- Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
- Measure the resistance of the (V937) Speed Control Switch Ground circuit between the Speed Control Switch harness connector and the BCM C8 harness connector.