GM Service Manual Online
For 1990-2009 cars only

Object Number: 413307  Size: MF
ABS Components
Cell 44: Wheel Speed Sensors and Variable Steering Actuator
Handling ESD Sensitive Parts Notice

Circuit Description

The wheel speed sensor used on this vehicle is a single point magnetic pickup. This sensor produces an AC signal that the EBTCM uses the frequency from to calculate the wheel speed.

Conditions for Setting the DTC

All of the following conditions exists for 2.5 seconds:

    • The suspect wheel speed equals zero.
    • The other wheel speeds are greater than 8 km/h (5 mph).
    • The other wheel speeds are within 11 km/h (7 mph) of each other.

Action Taken When the DTC Sets

    • A malfunction DTC is stored.
    • The ABS/TCS/Stabilitrak® is disabled.
    • The ABS indicator is turned ON.
    • The TRACTION CONTROL indicator is turned ON.
    • The DIC displays the SERVICE STABILITY SYS message.

Conditions for Clearing the DTC

    • The condition for DTC is no longer present and you used scan tool Clear DTCs function.
    • The condition for DTC is no longer present and you used the On-Board Clear DTCs function.
    • The EBTCM does not detect the DTC in 50 drive cycles.

Diagnostic Aids

    • Perform a thorough inspection of the wiring and the connectors. Failure to carefully and fully inspect wiring and connectors may result in misdiagnosis, causing part replacement with reappearance of the malfunction.
    • An intermittent malfunction may be caused by poor connections, broken insulation, or a wire that is broken inside the insulation.
    • If an intermittent malfunction exists, refer to Intermittents and Poor Connections .

Test Description

The numbers below refer to step numbers on the diagnostic table.

  1. This step tests the resistance of the WSS.

  2. This step tests if the WSS circuits are shorted together.

DTC C1222 RF Wheel Speed Sensor Input is 0

Step

Action

Value(s)

Yes

No

1

Was the Diagnostic System Check performed?

--

Go to Step 2

Go to Diagnostic System Check

2

  1. Inspect the wheel speed sensor (WSS) wiring and the connectors for damage.
  2. Inspect the WSS for looseness or damage.

Is physical damage of sensor evident?

--

Go to Step 7

Go to Step 3

3

  1. Disconnect the WSS at the sensor pigtail.
  2. Using the J 39200 digital multimeter (DMM), measure the resistance between terminal A and terminal B of the WSS.

Is the resistance within the specified range?

850-1350 ohms

Go to Step 4

Go to Step 7

4

  1. With the J 39200 DMM still connected, select the mV AC scale.
  2. Spin the wheel as fast as you can by hand while monitoring the AC output.

Is the AC voltage greater than the specified value?

100 mV

Go to Step 5

Go to Step 7

5

  1. Disconnect the EBTCM harness connector.
  2. Install the J 39700 universal pinout box using the J 39700-25 cable adapter to the EBTCM harness connector only.
  3. Using the J 39200 DMM, measure resistance between terminal 14 and terminal 30 of the J 39700 .

Is the resistance equal to the specified value?

OL (Infinite)

Go to Step 6

Go to Step 8

6

  1. Reconnect all of the connectors.
  2. Carefully test drive vehicle above 24 km/h (15 mph) for at least 30 seconds while monitoring a scan tool.

Does the DTC reset as a current DTC?

--

Go to Step 9

Go to Diagnostic System Check

7

Replace the wheel speed sensor. Refer to Front Wheel Bearing and Hub Replacement in Front Suspension.

Did you complete the repair?

--

Go to Step 10

--

8

Repair short between CKT 833 and CKT 872. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Step 10

--

9

Replace EBTCM. Refer to Electronic Brake Control Module Replacement .

Is the replacement complete?

--

Go to Step 10

--

10

Carefully test drive vehicle above 24 km/h (15 mph) while monitoring a scan tool for at least 30 seconds.

Does the DTC set as a current DTC?

--

Go to Step 2

Go to Diagnostic System Check