For 1990-2009 cars

### Diagnostic Instructions

• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

• | Review Strategy Based Diagnosis for an overview of the diagnostic approach.

• | Diagnostic Procedure Instructions provides an overview of each diagnostic category.

### DTC Descriptors

DTC C0186 00: Lateral Accelerometer Circuit
DTC C0186 3B: Lateral Accelerometer Self Test Failure
DTC C0186 4B: Lateral Accelerometer Calibration Not Learned
DTC C0186 5A: Lateral Accelerometer Circuit Plausibility Failure
DTC C0196 00: Yaw Rate Circuit
DTC C0196 3B: Yaw Rate Self Test Failure
DTC C0196 4B: Yaw Rate Calibration Not Learned
DTC C0196 5A: Lateral Accelerometer Circuit Plausibility Failure

### Diagnostic Fault Information

Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance
--- | --- | --- | --- | ---
12 Volt Reference | C0186 00, C0196 00 U2142 00 | C0186 00, C0196 00 U2142 00 | -- | C0186 00, C0186 3B, C0186 4B, C0186 5A, C0196 00, C0196 3B, C0196 4B, C0196 5A, U2142 00
Low Reference | C0186 00, C0196 00 U2142 00 | C0186 00, C0196 00 U2142 00 | C0186 00, C0196 00 U2142 00 | C0186 00, C0186 3B, C0186 4B, C0186 5A, C0196 00, C0196 3B, C0196 4B, C0196 5A, U2142 00
CAN Bus High Serial Data | C0186 00, C0196 00 U2142 00 | C0186 00, C0196 00 U2142 00 | C0186 00, C0196 00 U2142 00 | C0186 00, C0186 3B, C0186 4B, C0186 5A, C0196 00, C0196 3B, C0196 4B, C0196 5A, U2142 00
CAN Bus Low Serial Data | C0186 00, C0196 00 U2142 00 | C0186 00, C0196 00 U2142 00 | C0186 00, C0196 00 U2142 00 | C0186 00, C0186 3B, C0186 4B, C0186 5A, C0196 00, C0196 3B, C0196 4B, C0196 5A, U2142 00

### Circuit/System Description

The yaw rate and the lateral accelerometer sensors are combined into one component. The vehicle stability enhancement system (VSES) uses the lateral accelerometer input when calculating the desired yaw rate. The yaw rate/lat sensor communicates with the EBCM via discrete CAN Bus High and CAN Bus Low serial data circuits.

### Conditions for Running the DTC

Ignition ON.

### Conditions for Setting the DTC

• | Short to voltage, a short to ground, or open/high resistance on the CAN High serial data circuit.

• | Short to voltage,a short to ground, or open/high resistance on the CAN Low serial data circuit.

• | The yaw/lateral combination sensor fails an internal self test.

• | The correlation error between the yaw/lateral combination sensor and steering angle sensor.

### Action Taken When the DTC Sets

• | The EBCM disables the antilock brake system (ABS)/traction control system (TCS) and vehicle stability enhancement system (VSES) for the duration of the ignition cycle.

• | A DIC message and/or a warning indicator may be displayed.

### Conditions for Clearing the DTC

• | The condition for the DTC is no longer present.

• | The EBCM clears the history DTC when a current DTC is not detected in 100 consecutive drive cycles.

### Reference Information

#### Schematic Reference

Antilock Brake System Schematics

#### Connector End View Reference

Component Connector End Views

#### Description and Operation

ABS Description and Operation

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

#### Scan Tool Reference

Control Module References for scan tool information

### Circuit/System Verification

1. Verify that DTC C0186 4B or C0196 4B is not set.

⇒ | If the DTC is set, with the scan tool perform the yaw/lat sensor calibration.

2. Clear DTC and operate the vehicle within the conditions for running the DTC. Verify the DTC does not reset.

⇒ | If the DTC resets, refer to circuit testing.

### Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the Yaw Rate/Lateral Accelerometer sensor.
2. Ignition OFF for 60 seconds, test for less than 10 Ω between the low reference circuit terminal 5 and ground.

⇒ | If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the EBCM.

3. Ignition ON, verify a test lamp illuminates between the 12 volt reference circuit terminal 3 and ground.

⇒ | If the test lamp does not illuminate, test the 12 volt reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the EBCM.

4. Ignition OFF, disconnect the harness connector at the steering angle sensor.
5. Ignition ON, test for less than 1 volt between the following serial data circuit terminal listed below and ground.

• | CAN Bus High Serial Data circuit terminal 2

• | CAN Bus Low Serial Data circuit terminal 1

⇒ | If greater than the specified range, test the serial data circuit for a short to voltage.

6. Ignition OFF, test for infinite resistance between the serial data circuit terminal listed below and ground.

• | CAN Bus High Serial Data circuit terminal 2

• | CAN Bus Low Serial Data circuit terminal 1

⇒ | If less than the specified value, test the serial data circuit for a short to ground.

7. Test for less than 2 Ω between the serial data circuit terminals listed below.

• | CAN Bus High Serial Data circuit terminal 2 at the steering position sensor harness connector and terminal 2 at the yaw rate sensor harness connector.

• | CAN Bus Low Serial Data circuit terminal 5 at the steering position sensor harness connector and terminal 1 at the yaw rate sensor harness connector.

⇒ | If greater than the specified range, test the serial data circuit for an open/high resistance.

8. If all circuits test normal, replace the yaw/lat sensor. If the DTC resets, replace the EBCM.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Vehicle Yaw Sensor Replacement