GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The electronic brake control module (EBCM) supplies a reference voltage of 5 volts to the yaw rate sensor/lateral accelerometer, the steering wheel position sensor and the master cylinder pressure sensor. The sensor supply voltage is monitored via an internal feedback circuit to the EBCM microprocessor.

DTC Descriptors

This diagnostic procedure supports the following DTCs:

    • DTC C0290 Devise Voltage Reference Output Circuit
    • DTC C0292 Devise Voltage Reference Input Circuit

Conditions for Running the DTC

The ignition is ON.

Conditions for Setting the DTC

The EBCM detects that the sensor supply voltage is less than 4.75 volts or greater than 5.25 volts for 30 milliseconds.

Action Taken When the DTC Sets

    • The EBCM disables the vehicle stability enhancement system (VSES).
    • The stability system caution indicator turns ON.

Test Description

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

  1. This step tests for a shorted yaw rate sensor/lateral accelerometer or steering wheel position sensor.

  2. This step tests for a shorted master cylinder pressure sensor. The presence of DTC C0110 is normal during this step.

Step

Action

Yes

No

Schematic Reference: Antilock Brake System Schematics

Connector End View Reference: Antilock Brake System Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

  1. Use the scan tool to clear the DTCs.
  2. Turn OFF the ignition for 5 seconds.
  3. Turn ON the ignition.

Does the DTC reset?

Go to Step 3

Go to Diagnostic Aids

3

  1. Turn OFF the ignition.
  2. Disconnect the yaw rate sensor/lateral accelerometer harness connector. Refer to Vehicle Yaw Sensor with Vehicle Lateral Accelerometer Replacement .
  3. Disconnect the steering wheel position sensor harness connector. Refer to Steering Wheel Position Sensor or Steering Shaft Lower Bearing Replacement .
  4. Disconnect the electronic brake control module (EBCM) harness connector. Refer to Control Module References .
  5. Test the yaw rate sensor/lateral accelerometer 5-volt reference circuit and the steering wheel position sensor 5-volt reference circuit for a short to ground.

Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 12

Go to Step 4

4

  1. Turn ON the ignition.
  2. Test the following circuits for a short to voltage:
  3. • Yaw rate sensor/lateral accelerometer 5-volt reference circuit
    • Steering wheel position sensor 5-volt reference circuit
    • Yaw rate sensor signal circuit
    • Lateral accelerometer signal circuit
    •  Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 12

Go to Step 5

5

  1. Turn OFF the ignition.
  2. Reconnect only the EBCM harness connector.
  3. Turn ON the ignition.
  4. Use the scan tool to clear any DTCs.

Does the DTC reset?

Go to Step 6

Go to Step 8

6

  1. Turn OFF the ignition.
  2. Reconnect the yaw rate sensor/lateral accelerometer harness connector.
  3. Reconnect the steering wheel position sensor harness connector.
  4. Separate the EBCM from the brake pressure modulator valve (BPMV), leaving the EBCM harness connector connected. Refer to Control Module References .
  5. Turn ON the ignition.

Does the DTC reset?

Go to Step 11

Go to Step 7

7

Replace the BPMV. Refer to Control Module References .

Did you complete the replacement?

Go to Step 12

--

8

Reconnect the steering wheel position sensor harness connector.

Does the DTC reset?

Go to Step 10

Go to Step 9

9

Important: Replace the lateral accelerometer/yaw rate sensor. Use the scan tool to perform a Yaw Rate Sensor Recalibration procedure.

Replace the yaw rate sensor/lateral accelerometer. Refer to Vehicle Yaw Sensor with Vehicle Lateral Accelerometer Replacement .

Did you complete the replacement?

Go to Step 12

--

10

Replace the steering wheel position sensor. Refer to Steering Wheel Position Sensor or Steering Shaft Lower Bearing Replacement .

Did you complete the replacement?

Go to Step 12

--

11

Important: Following EBCM replacement, perform the setup procedure for the EBCM. Use the scan tool to perform the Tire Size Calibration procedure.

Replace the EBCM. Refer to Control Module References .

Did you complete the replacement?

Go to Step 12

--

12

  1. Use the scan tool Clear All serial data DTCs function to clear all of the DTCs from all modules.
  2. Turn OFF the ignition for 5 seconds.
  3. Turn ON the ignition.
  4. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.

Does the DTC reset?

Go to Step 3

System OK