Circuit Description
As the wheel spins, the wheel speed sensor produces an AC voltage signal. The electronic brake control module (EBCM) uses the frequency of the AC signal to calculate the wheel speed.
DTC Descriptors
This diagnostic procedure supports the following DTCs:
| • | DTC C0035 Left Front Wheel Speed Sensor Circuit |
| • | DTC C0036 Left Front Wheel Speed Sensor Circuit Range/Performance |
| • | DTC C0037 Let Front Wheel Speed Sensor Circuit Low |
| • | DTC C0040 Right Front Wheel Speed Sensor Circuit |
| • | DTC C0041 Right Front Wheel Speed Sensor Circuit Range/Performance |
| • | DTC C0042 Right Front Wheel Speed Sensor Circuit Low |
| • | DTC C0046 Left Rear Wheel Speed Sensor Circuit Range/Performance |
| • | DTC C0047 Left Rear Wheel Speed Sensor Circuit Low |
| • | DTC C0051 Right Rear Wheel Speed Sensor Circuit Range/Performance |
| • | DTC C0052 Right Rear Wheel Speed Sensor Circuit Low |
Conditions for Running the DTC
C0035, C0040, C0045 and C0050
The ignition is ON.
C0036, C0037, C0041, C0042, C0046, C0047, C0051 and C0052
| • | The ignition is ON. |
| • | The vehicle speed is greater than 20 km/h (13 mph). |
Conditions for Setting the DTC
C0035, C0040, C0045 and C0050
The EBCM detects an open or shorted wheel speed sensor or wheel speed sensor circuit.
C0036, C0041, C0046 and C0051
The EBCM detects an erratic signal from the corresponding wheel speed sensor.
C0037, C0042, C0047 and C0052
The corresponding wheel speed sensor signal is 0 km/h (0 mph).
Action Taken When the DTC Sets
If equipped, the following actions occur.
| • | The EBCM disables the antilock brake system (ABS)/traction control system (TCS). |
| • | The ABS indicator turns ON. |
| • | The traction off indicator turns ON. |
Conditions for Clearing the DTC
When the conditions for setting the DTC are no longer present, the DTC can be cleared with a scan tool.
Diagnostic Aids
If debris is present between the teeth of the tone ring, the wheel speed sensor could be moved out of position and the air gap could become too large. Adjust the air gap if any debris is found on the tone ring.
Thoroughly inspect connections or circuitry that may cause an intermittent malfunction. Refer to the following:
If the customer concern is that the ABS indicator is ON only during humid conditions such as rain, snow, or vehicle wash, thoroughly inspect the wheel speed sensor circuits for signs of water intrusion. Use the following procedure in order to help isolate the problem area:
- Spray the suspected area with a 5 percent salt water solution.
- Drive the vehicle at a speed greater than 19 km/h (12 mph) for at least 30 seconds.
Repair or replace the suspect harness if the DTC sets.
Test Description
The numbers below refer to the step numbers on the diagnostic table.
-
Measures the resistance value of the wheel speed sensor in order to determine if the sensor has a valid resistance value.
-
Tests for the correct bearing play and exciter ring for tooth integrity. Runout shall not exceed 0.2 mm (0.008 in) at pitch. Excessive bearing play can cause the wheel speed sensor air gap to exceed specification. Replace components with exciter rings that are corroded or damaged. Wheel speed sensor air gap must be reinspected after a repair is made to correct excessive bearing play.
-
Ensures the wheel speed sensor is generating a valid AC voltage output.
-
Checks tone ring condition and sensor air gap.
-
Checks condition of wheel speed sensor wire leads, and connector.
-
Checks condition of EBCM connector.
Step | Action | Values | Yes | No | ||||
|---|---|---|---|---|---|---|---|---|
Schematic Reference: Antilock Brake System Schematics Connector End View Reference: Antilock Brake System Connector End Views | ||||||||
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | |||||
2 |
Does the DTC set? | 20 km/h (13 mph) | Go to Step 3 | Go to Diagnostic Aids | ||||
Is the resistance of the wheel speed sensor within the specified range? | 1,800-2,200 ohms | Go to Step 4 | Go to Step 8 | |||||
Did you find and correct the condition? | -- | Go to Step 13 | Go to Step 5 | |||||
Slowly spin the wheel by hand while using a DMM to measure the AC voltage across the wheel speed sensor. Does the AC voltage measure greater than the specified value? | 800 mV | Go to Step 7 | Go to Step 6 | |||||
Did you find and correct the condition? | 800 mV | Go to Step 13 | Go to Step 8 | |||||
Reconnect the wheel speed sensor connector. Disconnect the connector from the EBCM. Measure the voltage on the wheel speed sensor circuits at the EBCM harness connector. Slowly spin the wheel by hand while using a DMM to measure the AC voltage from the wheel speed sensor. Does the AC voltage measure greater than the specified value? | 800 mV | Go to Step 9 | Go to Step 10 | |||||
8 | Inspect for poor connections at the harness connector of the wheel speed sensor. 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 11 | ||||
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 . Did you find and correct the condition? | -- | Go to Step 13 | Go to Step 12 | |||||
10 | Repair the open or short in the wheel speed sensor circuits. Refer to Circuit Testing and Wiring Repairs . Did you complete the repair? | -- | Go to Step 13 | -- | ||||
11 | Replace the wheel speed sensor. Refer to Front Wheel Speed Sensor Replacement or Rear Wheel Speed Sensor Replacement . Did you complete the replacement? | -- | Go to Step 13 | -- | ||||
12 | Replace the EBCM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement? | -- | Go to Step 13 | -- | ||||
13 |
Does the DTC set? | -- | Go to Step 3 | System OK | ||||
