GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2007 🢒 Silverado Classic - 2WD 🢒 Safety and Security 🢒 Supplemental Inflatable Restraints 🢒 DTC C0245 or C0078

DTC C0245 or C0078 with rear drum brakes

Circuit Description

As the wheels spin, each wheel speed sensor produces an AC signal. The electronic brake control module (EBCM) uses the frequency of the AC signals to calculate each wheel speed.

DTC Descriptor

This diagnostic procedure supports the following DTCs:

    • DTC C0245 Wheel Speed Sensor Frequency Error
    • DTC C0078 Wheel Speed Sensor Frequency Error (PHT)

Conditions for Running the DTC
    • The ignition is ON.
    • The vehicle speed is greater than 8 km/h (4 mph).
    • No brake application or deceleration is detected.
    • No wheel slip is detected.
    • No turning maneuvers are detected.

Conditions for Setting the DTC
    • At least one wheel speed sensor signal is 15 percent less than or greater than other wheel speed sensor signals.
    • All of the Conditions for Running and Setting the DTC are present for a cumulative time of 3 minutes during a single ignition cycle.

Action Taken When the DTC Sets
    • The EBCM disables the ABS/traction control system (TCS)/vehicle stability enhancement system (VSES)/dynamic rear proportion (DRP).
    • The ABS indicator turns ON.
    • The traction off indicator turns ON.
    • The message center displays the service stability system message.
    • 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 in order to clear the DTCs.
  2. Turn OFF the ignition for 5 seconds.
  3. Turn ON the ignition.
  4. Operate the vehicle for at least 3 minutes within the Conditions for Running the DTC as specified in the supporting text.

Does the DTC reset?

Go to Step 2

System OK