GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The electronic brake control module (EBCM) supplies 5 volts to the yaw rate sensor/lateral accelerometer. When the vehicle is not moving, or is being driven in a stable, straight line, yaw rate is 0 degrees/second and the yaw rate sensor signal voltage is very near 2.5 volts. This is referred to as sensor bias voltage. Performing a turning maneuver causes the yaw rate sensor signal voltage to increase, or decrease, depending on the direction of the turn. The sharper the turn, the greater the change in signal voltage.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC C0196 Yaw Rate Circuit

Conditions for Running the DTC

    • The ignition is ON.
    • The vehicle stability enhancement system (VSES) sensors have been successfully initialized or the message center has displayed the stability system disabled message due to an unsuccessful initialization attempt. Refer to ABS Description and Operation for a complete explanation of VSES sensor initialization.
    • The vehicle is being driven relatively straight and level at a speed greater than 11 km/h (7 mph), before performing a stable turning maneuver.

Conditions for Setting the DTC

Any of the following conditions may cause the DTC to set:

    • Open yaw rate sensor circuitry is detected.
    • Shorted yaw rate sensor circuitry is detected.
    • An erratic yaw rate sensor signal is detected.
    • The EBCM detects that the yaw rate sensor signal does not correspond with signals from other sensors.

Action Taken When the DTC Sets

    • The EBCM disables the VSES.
    • The stability indicator turns ON.

Conditions for Clearing the DTC

The conditions for setting the DTC are no longer present and you use the scan tool Clear DTCs function.

Diagnostic Aids

    • The following scenario may cause this DTC to set when no actual malfunction exists:
       - The vehicle is driven in a straight line in reverse at a speed greater than 13 km/h (8 mph).
       - The transmission is shifted into neutral while the vehicle continues to coast backward.
       - A turning maneuver is performed after the above conditions are met and the vehicle speed is still greater than 13 km/h (8 mph).
    • This DTC may also set falsely if the yaw rate sensor is replaced without first following the diagnostic table below. Whenever a new yaw rate sensor is installed, the old sensor must be disconnected, the ignition turned ON for 5 seconds and then OFF, and then the new sensor connected.
    • Inspect the vehicle for proper wheel alignment. Ensure the vehicle does not pull toward the left or right while driving straight forward on a level surface.
    • Communicate with the customer to determine the conditions under which the message center displays the service stability system message. Learning the conditions under which the DTC sets may help you duplicate the failure.
    • Use the Snapshot function on the scan tool in order to assist you in locating an intermittent malfunction.

Test Description

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

  1. This step tests the sensor 5 volt reference circuitry and ground circuit.

  2. This step tests the sensor signal circuit for an open or high resistance.

Step

Action

Values

Yes

No

Important: If DTC C0292 is set, diagnose C0292 before proceeding with diagnostics for C0196.

Always use connector test adapters when performing tests to avoid damage to delicate connector terminals.

Do not turn OFF the ignition during this diagnostic procedure unless the step in the table instructs you to do so. The scan tool may display some incorrect data if the ignition is cycled.

Schematic Reference: Antilock Brake System Schematics

Connector End View Reference: Antilock Brake System Connector End Views

1

Did you perform the ABS 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.
  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

Go to Diagnostic Aids

3

  1. Turn ON the ignition switch.
  2. Use a DMM to measure the voltage between the yaw rate 5-volt reference circuit and the yaw rate low reference circuit.

Does the voltage measure greater than the specified value?

4.75 V

Go to Step 5

Go to Step 4

4

Test the yaw rate signal circuit for the following conditions:

    • An open
    • A high resistance
    • A short to ground

Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

--

Go to Step 9

Go to Step 6

5

  1. Inspect for poor connections at the harness connector of the yaw rate sensor/lateral accelerometer. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .
  2. Ensure the yaw rate sensor/lateral accelerometer is mounted securely and that the mounting bracket is not bent or otherwise damaged.

Did you find and correct the condition?

--

Go to Step 9

Go to Step 7

6

Inspect for poor connections at the harness connector of the electronic brake control module (EBCM). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

--

Go to Step 9

Go to Step 8

7

Important: Replace the lateral accelerometer/yaw rate sensor, Refer to EBCM reprogramming to verify current calibration (enabling Yaw Rate Sensor Recalibration). Use a scan tool to Recalibrate the Yaw Rate Sensor.

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

Did you complete the replacement?

--

Go to Step 9

--

8

Important: Following EBCM replacement, perform the set-up 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 9

--

9

  1. Use the scan tool Clear All Class 2 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