GM Service Manual Online
For 1990-2009 cars only

Circuit Description

As the wheels spin, each wheel speed sensor produces a digital square wave signal. The electronic brake control module (EBCM) uses the frequency of these signals to calculate each wheel speed.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC C0245 Wheel Speed Sensor Frequency Error

Conditions for Running the DTC

    • The ignition is ON.
    • The vehicle speed is between 22 km/h (14 mph) and 110 km/h (69 mph).
    • No brake application or deceleration is detected.
    • No wheel slip is detected.
    • No turning maneuvers are detected.

Conditions for Setting the DTC

The average front wheel speed differs from the rear wheel speed by at least 20 percent for 4 seconds.

Action Taken When the DTC Sets

    • The EBCM disables the Antilock Brake System (ABS)/traction control switch (TCS)/dynamic rear proportion (DRP).
    • The ABS Fault message is displayed.
    • The traction fault message is displayed.
    • The brake warning indicator turns ON.

Conditions for Clearing the DTC

The Conditions for Setting the DTC are no longer present and you use the scan tool Clear DTCs function.

Diagnostic Aids

Operating the vehicle with a tire that has very low air pressure may set this DTC.

Step

Action

Yes

No

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

Inspect all of the tires on the vehicle to ensure that all of the tires are of equal size.

Did you find and correct the condition?

Go to Step 4

Go to Step 3

3

Inspect the wheel speed sensors and tone rings for damage, incorrect application, or incorrect installation.

Did you find and correct the condition?

Go to Step 4

Go to Diagnostic Aids

4

  1. Use a scan tool to clear the DTCs.
  2. Operate the vehicle within the Conditions for Running the DTC, as specified in the supporting text.

Does the DTC reset?

Go to Step 2

System OK