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For 1990-2009 cars only

DTC C0223 or C023 RF Wheel Speed Signal Erratic 310 ABS

Circuit Description

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

Conditions for Running the DTC

    • Ignition switch in the RUN position.
    • All wheel speed sensor signals are greater than 32 km/h (20 mph) with brake applied or 19 km/h (12 mph) with brake released.

Conditions for Setting the DTC

Either of the following conditions will set DTC C0223.

    • A sudden loss of the corresponding wheel speed sensor signal is detected for 15 milliseconds.
    • A sudden increase is detected in the corresponding 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 lamp turns on.
    • The ABS disables 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.

Diagnostic Aids

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

Thoroughly inspect any connection or circuitry that is suspected of causing an intermittent malfunction. Inspect for the following conditions:

    • 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 says that the ABS indicator lamp is on only during humid conditions such as rain, snow, or vehicle wash, then thoroughly inspect all wheel speed sensor circuits for signs of water intrusion. Use the following procedure:

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

If the DTC returns, replace the suspected harness.

When inspecting a wheel speed sensor, inspect the sensor terminals and the harness connector for corrosion. If evidence of corrosion exists, then replace the wheel speed sensor. Refer to Wheel Speed Sensor Replacement .

Step

Action

Value(s)

Yes

No

Schematic References: Antilock Brake System Schematics

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 at a speed greater than the specified value.

Does the DTC set?

32 km/h (20 mph)

Go to Step 3

Go to Diagnostic Aids

3

  1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  2. Disconnect the wheel speed sensor connector.
  3. Use a DMM in order to measure the resistance of the wheel speed sensor.

Does the resistance measure within the specified range?

700-2000ohms

Go to Step 4

Go to Step 8

4

  1. Spin the wheel by hand as fast as possible.
  2. Use a DMM in order to measure the AC voltage generated by the wheel speed sensor as the wheel spins.

Does the AC voltage measure greater than the specified value?

100 mV

Go to Step 5

Go to Step 8

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 10

Go to Step 6

6

Test the wheel speed sensor circuits for the following:

  1. An open
  2. A short to ground
  3. A short to voltage
  4. Shorted together

Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 10

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 10

Go to Step 9

8

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

Did you complete the replacement?

--

Go to Step 10

--

9

Important: Perform the tire size calibration in Scan Tool Diagnostics

Replace the EBCM. Refer to Electronic Brake Control Module Replacement .

Did you complete the replacement?

--

Go to Step 10

--

10

  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle at a speed greater than the specified value.

Does the DTC reset?

32 km/h (20 mph

Go to Step 2

System OK

DTC C0223 or C023 RF Wheel Speed Signal Erratic 325 ABS

Circuit Description

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

Conditions for Running the DTC

    • Ignition switch in the RUN position.
    • All wheel sped sensor signals are greater than 32 km/h (20 mph) with brake applied or 19 km/h (12 mph) with brake released.

Conditions for Setting the DTC

Either of the following conditions will set DTC C0223.

    • A sudden loss of the corresponding wheel speed sensor signal is detected for 15 milliseconds.
    • A sudden increase is detected in the corresponding 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 lamp turns on.
    • The ABS disables 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 will remain 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 cause DTC C0223 to set even though the system is not malfunctioning.

Thoroughly inspect any connection or circuitry that is suspected of causing an intermittent malfunction. Inspect for the following conditions:

    • 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 says that the ABS indicator lamp is on only during humid conditions such as rain, snow, or vehicle wash, then thoroughly inspect all wheel speed sensor circuits for signs of water intrusion. Use the following procedure:

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

If the DTC returns, replace the suspected harness.

When inspecting a wheel speed sensor, inspect the sensor terminals and the harness connector for corrosion. If evidence of corrosion exists, then replace the wheel speed sensor. Refer to Wheel Speed Sensor Replacement .

Step

Action

Value(s)

Yes

No

Schematic References: Antilock Brake System Schematics

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 at a speed greater than the specified value.

Does the DTC set?

8 km/h (5 mph)

Go to Step 3

Go to Diagnostic Aids

3

  1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  2. Disconnect the wheel speed sensor connector.
  3. Use a DMM in order to measure the resistance of the wheel speed sensor.

Does the resistance measure within the specified range?

700-2000ohms

Go to Step 4

Go to Step 8

4

  1. Spin the wheel by hand as fast as possible.
  2. Use a DMM in order to measure the AC voltage generated by the wheel speed sensor as the wheel spins.

Does the AC voltage measure greater than the specified value?

100 mV

Go to Step 5

Go to Step 8

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 10

Go to Step 6

6

Test the wheel speed sensor circuits for the following:

  1. An open
  2. A short to ground
  3. A short to voltage
  4. Shorted together

Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 10

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 10

Go to Step 9

8

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

Did you complete the replacement?

--

Go to Step 10

--

9

Important: Perform the tire size calibration in Scan Tool Diagnostics

Replace the EBCM. Refer to Electronic Brake Control Module Replacement .

Did you complete the replacement?

--

Go to Step 10

--

10

  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle at a speed greater than the specified value.

Does the DTC reset?

32 km/h (20 mph

Go to Step 2

System OK