GM Service Manual Online
For 1990-2009 cars only
Table 1: WSS Temperature vs. Sensor Resistance

Object Number: 366393  Size: MF
ABS Components
Antilock Brake System Schematics

Circuit Description

The wheel speed sensor coil emits an electromagnetic field. A toothed ring on the wheel passes by the wheel speed sensor and disrupts this electromagnetic field. The disruption in the field causes the wheel speed sensor to produce a sinusoidal (AC) voltage signal. The frequency and amplitude of the sinusoidal (AC) voltage signal are proportional to the speed of the wheel. The amplitude of the wheel speed signal is also directly related to the distance between the wheel speed sensor coil and the toothed ring. This distance is referred to as the air gap.

Conditions for Setting the DTC

The wheel speed signal for all sensors is above 19 km/h (12 mph) with brake released, or 32 km/h (20 mph) with brake applied, with a sudden loss of one signal for 15 ms.

Action Taken When the DTC Sets

    • The ABS indicator lamp turns on
    • The ABS disables

DTC C0223 is Condition Latched for the first two occurrences, Ignition Latched thereafter.

DTC C0223 is a DRP non critical malfunction. If another front WSS DTC sets before this DTC is investigated and cleared, this will become a DRP Critical malfunction and the BRAKE indicator lamp will also turn on.

Conditions for Clearing the DTC

    • Repair the conditions responsible for setting the DTC
    • Use the Scan Tool Clear DTCs function
    • A Condition Latched DTC may exist momentarily, or constantly. In either case, the DTC will be stored in the EBCM memory until it is repaired, and/or the DTC is cleared. After the DTC is repaired and/or cleared and the ignition is turned to ON, the ABS lamp will remain lit until the EBCM completes a power-up self test. This test concludes when the vehicle has reached a speed of greater than 13 km/h (8 mph) and the wheel speed inputs have been checked by the EBCM.

Diagnostic Aids

Any of the following conditions may cause an intermittent malfunction:

    • A poor connection
    • Wire insulation that is rubbed through
    • A wire breaks inside the insulation

Thoroughly check any circuitry that is suspected of causing the intermittent complaint for the following conditions:

    • Backed out terminals
    • Improper mating
    • Broken locks
    • Improperly formed or damaged terminals
    • Poor terminal to wiring connections
    • Physical damage to the wiring harness

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 .

Resistance of the wheel speed sensor will increase with an increase in sensor temperature. Refer to the following table for temperature/resistance values.

WSS Temperature vs. Sensor Resistance

°C

°F

Ohms

Temperature vs Resistance Values (Approximate)

-40 to 4

-40 to 40

702 to 1060

5 to 43

41 to 110

855 to 1230

44 to 93

111 to 200

1000 to 1440

94 to 150

201 to 302

1170 to 1661

Test Description

The numbers below refer to the steps in the diagnostic table:

  1. This step checks for the proper wheel speed sensor voltage output.

  2. This step uses the wheel speed sensor resistance check to help isolate an intermittent connection.

  3. This step checks to see if the DTC will set again even after the initial checks were made.

  4. This step checks for proper wheel speed sensor resistance.

  5. This step checks for proper mounting and orientation of the wheel speed sensor.

Step

Action

Value(s)

Yes

No

1

Was the Diagnostic System Check performed?

--

Go to Step 2

Go to Diagnostic System Check - ABS

2

  1. Turn the ignition to OFF.
  2. Disconnect the 16-way EBCM harness connector and inspect for signs of damage or corrosion.
  3. Inspect the wheel speed sensor harness and sensor harness connector for signs of damage or corrosion.

Are all connections clean and tight?

--

Go to Step 3

Go to Step 8

3

  1. Install a J 39700 and J 39700-325 on the 16-way EBCM harness connector.
  2. Raise the wheel from the ground.
  3. Rotate the wheel by hand at a constant speed.
  4. Using a J 39200 , measure the output voltage of the WSS between terminals A3 and B3 of the 16-way EBCM harness connector by probing between terminals 3 and 11 in the J 39700.

Is the voltage measurement within the specified range?

.6 - 1 VAC

Go to Step 4

Go to Step 7

4

Using a J 39200 , measure the resistance between terminals A3 and B3 of the 16-way EBCM harness connector by probing between terminals 3 and 11. Wiggle the WSS harness in various locations between the sensor and the EBCM while performing this measurement.

Is the resistance measurement within the specified range without fluctuation when the harness is wiggled? (Refer to the WSS Temperature vs. Resistance table for applicable sensor resistance values. The values in this table are for the temperature of the sensor, not the air temperature.)

--

Go to Step 5

Go to Step 6

5

  1. Reconnect all connectors.
  2. Clear DTC C0223 with the Scan Tool.
  3. Test Drive the vehicle at greater than 13 km/h (8 mph).

Does DTC C0223 set as a current DTC?

--

Go to Step 7

Go to Step 11

6

  1. Disconnect the wheel speed sensor from the wheel speed sensor harness connector.
  2. Using a J 39200 , measure the resistance between terminals A and B of the right front wheel speed sensor.

Is the resistance measurement within the specified range? (Refer to the WSS Temperature vs. Resistance table for applicable sensor resistance values. The values in this table are for the temperature of the sensor, not the air temperature.)

--

Go to Step 9

Go to Step 10

7

  1. Remove tire and wheel. Refer to Tire and Wheel Removal and Installation .
  2. Inspect the WSS attachment to the hub/bearing assembly.
  3. Verify that the wheel speed sensor is securely mounted.

Is the wheel speed sensor securely mounted?

--

Go to Step 13

Go to Step 12

8

Make necessary repairs to the 16-way EBCM harness connector. Refer to Repairing Connector Terminals .

Is the repair complete?

--

Go to Diagnostic System Check - ABS

--

9

Repair the open, high resistance or short in CKT 872.

Is the repair complete?

--

Go to Diagnostic System Check - ABS

--

10

Replace the right front wheel speed sensor.

Refer to Wheel Speed Sensor Replacement .

Is the repair complete?

--

Go to Diagnostic System Check - ABS

--

11

Malfunction is intermittent. Inspect all connectors for damage which may result in high resistance when all components are connected. Refer to Diagnostic aids for more information. Repair all damage found.

Is the repair complete?

--

Go to Diagnostic System Check - ABS

--

12

Make necessary repairs.

Refer to Wheel Speed Sensor Replacement .

Is the repair complete?

--

Go to Diagnostic System Check - ABS

--

13

Replace the Electronic Brake Control Module.

Refer to Electronic Brake Control Module Replacement .

Is the repair complete?

--

Go to Diagnostic System Check - ABS

--