Circuit Description
The ignition 3 voltage circuit supplies 12 volts to the traction control switch. The electronic brake control module (EBCM) turns OFF the Traction Off indicator by applying ground to the service traction control signal circuit.
Diagnostic Aids
The contacts within the traction control switch may intermittently fail. Press and release the traction control switch while observing the scan tool to verify a change in the status of the Traction Control Enabled parameter.
Thoroughly inspect connections or circuitry that may cause an intermittent malfunction. Refer to the following:
Test Description
The number below refers to the step number on the diagnostic table.
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Antilock Brake System Schematics | |||
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | |
2 |
Does the Traction Off indicator illuminate for 3 seconds and then turn OFF? | Go to Step 3 | Go to Step 5 |
3 | Press and release the traction control switch. Does the Traction Off indicator turn ON? | Go to Diagnostic Aids | Go to Step 4 |
4 | Press and release the traction control switch while observing the Traction Control Enabled status on the scan tool. Does the Traction Control Enabled status change when the switch is pressed? | Go to Step 12 | Go to Step 6 |
5 |
Does the test lamp illuminate? | Go to Step 7 | Go to Step 8 |
Does the Traction Control System status change when the test lamp is momentarily connected? | Go to Step 8 | Go to Step 9 | |
7 |
Did you find and correct the condition? | Go to Step 13 | Go to Step 12 |
8 | Inspect for poor connections at the harness connector of the traction control 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 10 |
9 | Test the traction control switch signal circuit for an open or a short to voltage. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | Go to Step 13 | Go to Step 11 |
10 | Replace the traction control switch. Refer to Electronic Traction Control Switch Replacement . Did you complete the replacement? | Go to Step 13 | -- |
11 | Inspect for poor connections at the harness connector of the EBCM. 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 |
12 | Replace the EBCM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement? | Go to Step 13 | -- |
13 | Press and release the traction control switch several times. Does the traction off indicator turn ON and OFF each time the switch is pressed? | System OK | Go to Step 3 |
