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.
The ignition is in the ON position.
• | The ignition is in the ON position. |
• | Vehicle speed of 20 km/h (12 mph) or more. |
• | The ignition is in the ON position. |
• | Vehicle speed of 20 km/h (12 mph) or more. |
• | The ignition is in the ON position. |
• | Vehicle speed of 20 km/h (12 mph) or more. |
The EBCM detects one of the following conditions in the wheel speed sensor circuits:
• | An open |
• | A short to ground |
• | A short to voltage |
The EBCM detects noise in the wheel speed sensor signal for more than 5 seconds.
The EBCM detects low output voltage of the wheel speed sensor.
The EBCM detects a rapid change in the wheel speed which is determined to be unreasonable.
The following actions occur:
• | The EBCM disables the antilock brake system (ABS) for the duration of the ignition cycle. |
• | The ABS indicator turns ON. |
The condition responsible for setting the DTC no longer exists and the scan tool Clear DTCs function is used.
The condition responsible for setting the DTC no longer exists and the scan tool Clear DTCs function is used.
The condition responsible for setting the DTC no longer exists and the scan tool Clear DTCs function is used.
• | The condition responsible for setting the DTC no longer exists and the scan tool Clear DTCs function is used. |
• | After the DTC is cleared, the ABS indicator will remain ON until the vehicle is road tested to verify the repair. Once the vehicle has been driven at a speed above 16 km/h (10 mph) for 20 seconds with no malfunctions present, the EBCM will turn OFF the ABS indicator. |
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 rotor |
• | An internal EBCM malfunction |
If an intermittent malfunction exists, refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.
The numbers below refer to the step numbers 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 A Diagnostic System Check - ABS? | -- | Go to Step 2 | |||||||||
2 |
Important: Interruption or loss of communication with the scan tool may occur if speed exceeds 56 km/h (35 mph). Does the scan tool indicate that this wheel speed DTC set? | 45 km/h (28 mph) | Go to Step 3 | Go to Diagnostic Aids | ||||||||
Does the resistance measure within the specified range? | 920-1220 ohms | Go to Step 4 | Go to Step 10 | |||||||||
4 | Measure the resistance between the wheel speed sensor terminals and ground. Does the resistance measure greater than specified? | Greater than 1 M ohms | Go to Step 5 | Go to Step 10 | ||||||||
5 | 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 in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 13 | Go to Step 6 | ||||||||
6 |
Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 13 | Go to Step 7 | ||||||||
7 | Inspect for poor connections at the harness connector for 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 13 | Go to Step 8 | ||||||||
8 | Inspect the wheel speed sensor for damage. Is the wheel speed sensor damaged? | -- | Go to Step 10 | Go to Step 9 | ||||||||
9 | Inspect the wheel speed sensor rotor for damage. Is the wheel speed sensor rotor damaged? | -- | Go to Step 11 | Go to Step 12 | ||||||||
10 | 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 | -- | ||||||||
11 | Replace the wheel speed sensor rotor. Refer to Front Wheel Drive Shaft Replacement or Rear Wheel Drive Shaft Replacement in Wheel Drive Shafts or Rear Wheel Bearing and Hub Replacement in Rear Suspension. Did you complete the replacement? | -- | Go to Step 13 | -- | ||||||||
12 | Replace the brake pressure modulator valve (BPMV). Refer to Brake Pressure Modulator Valve Assembly Replacement . Did you complete the replacement? | -- | Go to Step 13 | -- | ||||||||
13 |
Does the DTC reset? | -- | Go to Step 2 | System OK |