Traction Off Indicator Always On W49
Circuit Description
The LED dimming supply circuit supplies voltage to the traction control switch. The EBCM turns OFF the traction off indicator by applying ground to the service traction control signal circuit, which causes the inverting driver module to open the traction control system passive indicator control circuit.
Diagnostic Aids
The traction control system can be controlled by the operator in the following ways:
| • | Through operation of the traction control switch. |
| • | Through programming of the traction control system automatic engagement feature. |
Depending on the programmed state, the operation of the traction control system, as well as the operation of the traction off and low traction indicators, differs. For a more detailed explanation of these operational characteristics, refer to Traction Control Indicator Lamps in ABS Description and Operation .
Observe the data list parameters listed below in order to determine the status of the traction control system when it is unknown if the system is operational.
| • | Traction Control Enabled |
| • | Traction Off Lamp Command |
Press the traction control switch and observe the scan tool in order to verify a change in the status of the data list parameters.
Thoroughly inspect connections or circuitry that may cause an intermittent malfunction. Refer to Testing for Intermittent Conditions and Poor Connections , Wiring Repairs and Connector Repairs in Wiring Systems.
Test Description
The numbers below refer to the step numbers on the diagnostic table.
-
This step simulates pressing and releasing a properly functioning traction control switch.
-
The traction control switch may be damaged if the traction control switch signal circuit is shorted to voltage.
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Antilock Brake System Schematics Connector End View Reference: Antilock Brake System Connector End Views | |||
1 | Did you perform the ABS Diagnostic System Check? | Go to Step 2 | |
2 |
Does the traction off indicator illuminate for 3 seconds and then turn OFF? | Go to Diagnostic Aids | Go to Step 3 |
3 | Press and release the traction control switch. Does the traction off indicator turn OFF? | Go to Diagnostic Aids | Go to Step 4 |
4 |
Does the Traction Control Enabled status change? | Go to Step 5 | Go to Step 11 |
5 |
Does the scan tool display Traction Off Lamp Command - On? | Go to Step 19 | Go to Step 6 |
6 | Remove the circuit board from the inverting driver module. Does the traction off indicator turn OFF? | Go to Step 8 | Go to Step 7 |
7 | Test the traction control system passive indicator control circuit 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 20 | Go to Step 15 |
8 | At the inverting driver module case, connect a test lamp between the ignition 1 voltage circuit and the ground circuit. Does the test lamp illuminate? | Go to Step 10 | Go to Step 9 |
9 | Test the igniton 1 voltage circuit and the ground circuit for opens and repair as necessary. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 20 | -- |
10 | At the inverting driver module case, connect a test lamp between the service traction control signal circuit and the ignition 1 circuit. Does the test lamp illuminate? | Go to Step 16 | Go to Step 12 |
|
Important: Do not disconnect the traction control switch harness connector during this step.
Does the Traction Control Enabled status change? | Go to Step 13 | Go to Step 14 | |
12 | Test the service traction control signal circuit for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 20 | Go to Step 18 |
13 | 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 20 | Go to Step 15 |
Test the traction control switch signal circuit for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 20 | Go to Step 19 | |
15 | Replace the traction control switch. Refer to Electronic Traction Control Switch Replacement . Did you complete the replacement? | Go to Step 20 | -- |
16 | Inspect for poor connections at the inverting driver module circuit board. 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 20 | Go to Step 17 |
17 | Replace the inverting driver module. Did you complete the replacement? | Go to Step 20 | -- |
18 | Inspect for poor connections at the harness connector of the 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 20 | Go to Step 19 |
19 |
Important: Following EBCM replacement, use the scan tool to perform the Tire Size Calibration procedure. Replace the EBCM. Refer to Electronic Brake Control Module Replacement . Did you complete the replacement? | Go to Step 20 | -- |
20 | 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 2 |
Traction Off Indicator Always On Except W49
Circuit Description
The ignition 1 voltage circuit supplies 12 volts to the traction control switch. The EBCM turns OFF the traction off indicator by applying ground to the service traction control signal circuit.
Diagnostic Aids
The traction control system can be controlled by the operator in the following ways:
| • | Through operation of the traction control switch. |
| • | Through programming of the traction control system automatic engagement feature. |
Depending on the programmed state, the operation of the traction control system, as well as the operation of the traction off and low traction indicators, differs. For a more detailed explanation of these operational characteristics, refer to Traction Control Indicator Lamps in ABS Description and Operation .
Observe the data list parameters listed below in order to determine the status of the traction control system when it is unknown if the system is operational.
| • | Traction Control Enabled |
| • | Traction Off Lamp Command |
Press the traction control switch and observe the scan tool in order to verify a change in the status of the data list parameters.
Thoroughly inspect connections or circuitry that may cause an intermittent malfunction. Refer to Testing for Intermittent Conditions and Poor Connections , Wiring Repairs and Connector Repairs in Wiring Systems.
Test Description
The numbers below refer to the step numbers on the diagnostic table.
-
This step simulates pressing and releasing a properly functioning traction control switch.
-
The traction control switch may be damaged if the traction control switch signal circuit is shorted to voltage.
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Antilock Brake System Schematics Connector End View Reference: Antilock Brake System Connector End Views | |||
1 | Did you perform the ABS Diagnostic System Check? | Go to Step 2 | |
2 |
Does the traction off indicator illuminate for 3 seconds and then turn OFF? | Go to Diagnostic Aids | Go to Step 3 |
3 | Press and release the traction control switch. Does the traction off indicator turn OFF? | Go to Diagnostic Aids | Go to Step 4 |
4 |
Does the Traction Control Enabled status change? | Go to Step 5 | Go to Step 7 |
5 |
Does the scan tool display Traction Off Lamp Command - On? | Go to Step 13 | Go to Step 6 |
6 |
Important: Do not disconnect the traction control switch harness connector during this step. Ensure the ignition is turned ON for the duration of this step.
Does the test lamp illuminate? | Go to Step 9 | Go to Step 8 |
|
Important: Do not disconnect the traction control switch harness connector during this step.
Does the Traction Control Enabled status change? | Go to Step 11 | Go to Step 10 | |
8 | Test the service traction control signal circuit for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 14 | Go to Step 12 |
9 | 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 14 | Go to Step 11 |
Test the traction control switch signal circuit for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 14 | Go to Step 13 | |
11 | Replace the traction control switch. Refer to Electronic Traction Control Switch Replacement . Did you complete the replacement? | Go to Step 14 | -- |
12 | Inspect for poor connections at the harness connector of the 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 14 | Go to Step 13 |
13 |
Important: Following EBCM replacement, use the scan tool to perform the Tire Size Calibration procedure. Replace the EBCM. Refer to Electronic Brake Control Module Replacement . Did you complete the replacement? | Go to Step 14 | -- |
14 | 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 2 |
