Circuit Description
The Traction Off indicator is controlled by the instrument panel cluster (IPC) via serial data messages from the electronic brake control module (EBCM). When the EBCM sees the traction control switch input grounded through the momentary traction control switch, it then disables traction control and sends a serial data message to the instrument cluster to turn the Traction Off indicator ON. Each time the ignition is cycled from OFF to ON, the traction control system is enabled.
The following conditions will cause the Traction Off indicator to illuminate:
| • | The EBCM has disabled the TCS due to a DTC. |
| • | The driver manually disabling the Traction Control System (TCS) via the traction control switch. |
| • | The instrument cluster bulb check--When the ignition switch is turned to ON, the Traction Off indicator will turn ON for approximately 3 seconds and then turn OFF. |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
-
Use the scan tool to check the normal state of the Traction Off indicator control.
-
This step ensures that the instrument cluster can operate the Traction Off indicator.
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Antilock Brake System Schematics | |||
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
Does the scan tool display Off? | Go to Step 3 | Go to Step 12 | |
Does the Traction Off indicator illuminate during the bulb check and then turn OFF? | Go to Step 4 | Go to Step 13 | |
4 |
Does the Traction Switch parameter change state? | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems | Go to Step 5 |
5 | Does the scan indicate that the TCS Enable Status parameter is Enabled? | Go to Step 6 | Go to Step 7 |
6 |
Does the scan tool display Enabled? | Go to Step 11 | Go to Step 8 |
7 |
Does the scan tool display Enabled? | Go to Step 11 | Go to Step 9 |
8 | Test the signal circuit of the traction control switch for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 17 | Go to Step 12 |
9 | Test the signal circuit of the traction control switch 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 10 |
10 | Test the ground circuit of the traction control switch 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 12 |
11 | 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 in Wiring Systems. Did you find and correct the condition? | Go to Step 17 | Go to Step 14 |
12 | Inspect for poor connections at the harness connector of the electronic brake control module (EBCM). 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 |
13 | Inspect for poor connections at the harness connector of the IPC. 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 |
14 | Replace the traction control switch. Did you complete the replacement? | Go to Step 17 | -- |
15 | Replace the EBCM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming. Did you complete the repair? | Go to Step 17 | -- |
16 | Replace the IPC. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming. Did you complete the repair? | 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 |
