Circuit Description
As the wheel spins, the wheel speed sensor produces an alternating current (AC) 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 LF Wheel Speed Sensor Circuit |
| • | DTC C0040 RF Wheel Speed Sensor Circuit |
| • | DTC C0045 LR Wheel Speed Sensor Circuit |
| • | DTC C0050 RR Wheel Speed Sensor Circuit |
Conditions for Running the DTC
The ignition is in the ON position.
Conditions for Setting the DTC
The EBCM detects a short to voltage, open circuit or erratic signal fault condition in the wheel speed sensor signal circuit and/or wheel speed low reference circuit.
Action Taken When the DTC Sets
The following actions occur:
| • | The EBCM disables the antilock brake and traction control systems for the duration of the ignition cycle. |
| • | The ABS, TRAC OFF and BRAKE warning indicators turn ON. |
Conditions for Clearing the DTC
The condition responsible for setting the DTC no longer exists and the scan tool Clear DTCs function is used.
Diagnostic Aids
Thoroughly inspect the wiring and the connectors. An incomplete inspection of the wiring and the connectors may result in a misdiagnosis, causing a part replacement with the reappearance of the malfunction.
The following are possible causes of the malfunction:
| • | A short to ground or a short to voltage in the wheel speed sensor circuitry |
| • | An open or high resistance in the wheel speed sensor circuitry |
| • | A malfunctioning wheel speed sensor |
| • | A malfunctioning wheel speed sensor ring |
| • | An internal EBCM malfunction |
If an intermittent malfunction exists, refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.
Test Description
The number below refers to the step number on the diagnostic table.
Step | Action | Value(s) | 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 |
Did DTC C0035, C0040, C0045, or C0050 reset? | -- | Go to Step 3 | Go to Diagnostic Aids | ||||||||
3 |
Is the resistance as specified? | 1300-1800 ohms @ 20°C (68°F) | Go to Step 4 | Go to Step 8 | ||||||||
4 | Inspect the wheel speed sensor for damage. Is the wheel speed sensor damaged? | -- | Go to Step 10 | Go to Step 5 | ||||||||
5 | Inspect the wheel speed sensor rotor for damage. Is the wheel speed sensor rotor damaged? | -- | Go to Step 11 | Go to Step 6 | ||||||||
6 |
Is voltage greater than the specified value? | 100 mV | Go to Step 7 | Go to Step 8 | ||||||||
Test the wheel speed sensor circuits for the following:
Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | -- | Go to Step 13 | Go to Step 9 | |||||||||
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 10 | ||||||||
9 | Inspect for poor connections at the harness connector for 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 13 | Go to Step 12 | ||||||||
10 | Replace the appropriate wheel speed sensor. Refer to Front Wheel Bearing and Hub Replacement or Rear Wheel Speed Sensor Replacement . Did you complete the replacement? | -- | Go to Step 13 | -- | ||||||||
11 | Replace the appropriate wheel speed sensor rotor. Refer to Front Wheel Bearing and Hub Replacement or Rear Axle Shaft Replacement . Did you complete the replacement? | -- | Go to Step 13 | -- | ||||||||
12 | Replace the EBCM. Refer to Electronic Brake Control Module Replacement . Did you complete the replacement? | -- | Go to Step 13 | -- | ||||||||
13 |
Does the DTC reset? | -- | Go to Step 2 | System OK | ||||||||
