C0245

DTC C0245

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.

* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC C0245 00
- Wheel Speed Sensor Frequency

Circuit/System Description

The wheel speed sensor receives ignition voltage from the electronic brake control module (EBCM) and provides an output signal to the EBCM. As the wheel spins, the wheel speed sensor sends the EBCM a DC square wave signal, and uses the frequency of the square wave signal to calculate the wheel speed.

Conditions for Running the DTC

* Brake is not applied.

* Vehicle is not cornering.

* No wheel speed sensor faults exist.

* Ignition voltage is greater than 10 V.

Conditions for Setting the DTC

* If two or more wheel speed sensor faults are detected.

* The difference between the fastest and slowest wheel speed is greater than 5 percent.

* The electronic brake control module cannot determine a specific wheel speed sensor signal because of electrical interference.

Action Taken When the DTC Sets

* The ABS indicator turns ON.

* The red Brake indicator turns ON.

* The active handling indicator turns ON, if equipped.

* The driver information center displays SERVICE ANTILOCK BRAKES message.

* The driver information center displays SERVICE TRACTION SYSTEM message.

* The driver information center displays SERVICE ACTIVE HANDLING SYSTEM message, if equipped.

* The electronic brake control module disables the ABS, traction control, and stability control for the duration of the ignition cycle.

Conditions for Clearing the DTC

* When the condition for setting the DTC is no longer present.

* The history DTC will clear after 40 consecutive fault-free ignition cycles have occurred.

Note: During normal diagnostic and/or repair verification technicians may find that the ABS, Traction control and/or Stability control indicators may be ON with NO DTCs displayed by the electronic brake control module. Do not replace the electronic brake control module for this condition.

If the ABS, Traction control and/or Stability control indicators are ON with no DTCs set, perform the following steps:

1. Remove the key from the ignition, open and close the driver's door to turn off retained accessory power, and wait 60 seconds.

2. Ignition ON, if the ABS, Traction Control and/or Stability control indicators are still illuminated, operate the vehicle at speeds greater than 16 km/h (10 MPH) to complete the self test. The electronic brake control module should request all indicators to turn OFF.

3. If indicators remain ON with no DTCs set after the drive cycle, disconnect the battery for at least 60 seconds then reconnect the battery.

4. Operate the vehicle at speeds greater than 40 km/h (25 MPH), the electronic brake control module should request all the indicators to turn OFF.

Diagnostic Aids

* A vehicle using a space saver spare will not set this code.

* Check for electrical magnetic interference with the wheel speed sensor harness.

* If two or more wheel speed sensors are inoperative, diagnose each wheel speed sensor individually.

* If the customer comments that the ABS indicator is ON only during moist environmental conditions (rain, snow, vehicle wash, etc.), inspect the wheel speed sensor wiring for signs of water intrusion.

Reference Information

Schematic Reference

Antilock Brake System Schematics [1][2]Antilock Brakes / Traction Control Systems

Connector End View Reference

Component Connector End Views 5 Bow Lowered Switch (CM7)

Description and Operation

ABS Description and Operation Description and Operation

Electrical Information Reference

* Circuit Testing Circuit Testing

* Connector Repairs Connector Repairs

* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections

* Wiring Repairs Wiring Repairs

Scan Tool Reference

Control Module References Control Module References for scan tool information

Circuit/System Verification

1. Verify DTC C0035, C0040, C0045, or C0050 is not set.

• If any of the DTCs are set
Refer to Diagnostic Trouble Code (DTC) List - Vehicle Diagnostic Trouble Code (DTC) List - Vehicle.

• If none of the DTCs are set

2. Verify that all tires are of uniform size and matching brand.

• If not of uniform size or matching brand

1. Replace the mis-sized or non-matching brand tire.

2. Ignition ON.

3. Verify the DTC does not set while operating the vehicle within the Conditions for Running the DTC.

• If the DTC set, replace the electronic brake control module.

• If the DTC does not set

4. All OK.

• If all tires are of uniform size and matching brand

3. Refer to Diagnostic Aids.

Repair Instructions

Perform the Diagnostic Repair Verification Verification Tests after completing the repair.

Control Module References Control Module References for electronic brake control module replacement, programming and setup