GM Service Manual Online
For 1990-2009 cars only

Circuit Description

As the wheel spins, the wheel speed sensor produces an AC signal. The EBCM uses the frequency of the AC signal to calculate the wheel speed.

Conditions for Running the DTC

    • The ignition is ON.
    • All of the wheel speed sensor signals are greater than 32 km/h (20 mph) when the brake is applied or 19 km/h (12 mph) when the brake is released.

Conditions for Setting the DTC

Either of the following conditions will set DTC C0223:

    • A sudden loss of the right front wheel speed sensor signal is detected for 15 milliseconds.
    • A sudden increase is detected in the right front wheel speed sensor signal at a rate greater than 8.8 km/h (5.5 mph) for 105 milliseconds.

Action Taken When the DTC Sets

    • The ABS indicator is commanded on.
    • The ABS is disabled for as long as the malfunction is present. If the malfunction occurs 3 or more separate times, the ABS is disabled for the remainder of the ignition cycle.

Conditions for Clearing the DTC

    • Repair the condition(s) responsible for setting the DTC.
    • Use a scan tool in order to clear the DTC.
    • After the DTC is cleared and the ignition is ON, the ABS indicator remains on until the EBCM completes a power-up self-test. This test concludes when the vehicle reaches a speed of greater than 13 km/h (8 mph) and the wheel speeds are verified by the EBCM.

Diagnostic Aids

Driving the vehicle on extremely rough terrain can set DTC C0223 even if the system is not malfunctioning.

Thoroughly inspect connections or circuitry that may cause an intermittent malfunction. Inspect for the following:

    • Backed out terminals
    • Improper mating
    • Broken locks
    • Corrosion
    • Improperly formed or damaged terminals
    • Poor terminal-to-wiring connections
    • Physically damaged wiring
    • Wiring broken inside the insulation

If the customer's concern is that the ABS indicator is on only during humid conditions such as rain, snow or vehicle wash, thoroughly inspect the wheel speed sensor circuit(s) for signs of water intrusion. Use the following procedure to help isolate the problem area:

  1. Spray the suspected area with a 5% salt water solution (two teaspoons of salt to 12 oz. of water).
  2. Drive the vehicle at a speed greater than 24 km/h (15 mph) for at least 30 seconds.

Replace the suspect harness if the DTC sets.

Inspect the terminal cavity of the wheel speed sensor for corrosion. Replace the wheel speed sensor if corrosion exists. Refer to Wheel Speed Sensor Replacement

Step

Action

Value(s)

Yes

No

1

Did you perform the ABS Diagnostic System Check?

--

Go to Step 2

Go to Diagnostic System Check

2

  1. Use a scan tool in order to clear the DTC(s).
  2. Operate the vehicle within the Conditions for Running the DTC.

Does the DTC set?

--

Go to Step 3

Go to Diagnostic Aids

3

Inspect the wheel speed sensor circuit for any damage or condition that could cause an intermittent open, short to ground or short to voltage. Refer to Testing for Electrical Intermittents and Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 6

Go to Step 4

4

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 6

Go to Step 5

5

Replace the wheel speed sensor. Refer to Wheel Speed Sensor Replacement .

Did you complete the replacement?

--

Go to Step 6

--

6

  1. Use a scan tool in order to clear the DTC.
  2. Operate the vehicle within the Conditions for Running the DTC

Does the DTC set?

--

Go to Step 3

System OK