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 5A: Lateral Accelerometer Plausibility Failure
DTC C0196 00: Yaw Rate Circuit
DTC C0196 5A: Yaw Rate Circuit Plausibility Failure

### Diagnostic Fault Information

Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance
--- | --- | --- | --- | ---
B+ | C0186 00, C0196 00 | C0186 00, C0196 00 | -- | --
5 Volt Reference | C0186 00, C0196 00, | C0186 00, C0196 00, | C0196 00 | --
Yaw Rate Signal | C0196 00 | C0196 00 | C0196 00 | C0186 5A
Yaw Rate Sensor Test Control Signal | C0196 00 | C0196 00 | C0196 00 | C0196 5A
Combined Vehicle Inertial Sensor Signal | C0186 00 | C0186 00 | C0186 00 | --
Low Reference | -- | C0186 00. C0196 00 | -- | --

### Circuit/System Description

The lateral accelerometer and the yaw rate sensors are combined into one sensor external to the electronic brake control module (EBCM). The electronic stability program (ESP) uses the lateral accelerometer input when calculating the desired yaw rate.

### Conditions for Running the DTC

• | Ignition ON.

• | Ignition voltage is greater than 10 volts.

### Conditions for Setting the DTC

#### C0186 00

• | The EBCM detects a short to voltage, short to ground or an open/high resistance on the combined vehicle inertial sensor signal circuit

• | The EBCM detects a short to ground or an open/high resistance on the 5 volt reference circuit, or the ignition voltage circuit.

#### C0196 00

• | The EBCM detects a short to voltage, short to ground or an open/high resistance in the 5 volt reference circuit, yaw rate sensor test control signal circuit, or the yaw rate signal circuit.

• | The EBCM detects an open/high resistance in the ignition voltage circuit.

• | The EBCM detects an open/high resistance in the low reference circuit.

#### C0186 5A or C0196 5A

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

### Action Taken When the DTC Sets

• | The EBCM disables the 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 Testing

1. Ignition OFF, disconnect the harness connector at the yaw/lat sensor.
2. Ignition OFF for 60 seconds, test for less than 5 ohms between the low reference circuit terminal 6 and ground.

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

3. Ignition ON, test for B+ between the ignition voltage circuit terminal 3 and ground.

⇒ | If not the specified value, test the ignition voltage circuit for a short to ground or open/high resistance.

4. Ignition OFF, disconnect the harness connector at the EBCM.
5. Ignition ON, test for less than 1 volt between the 5 volt reference circuit terminal 1 at the yaw/lat sensor and ground.

⇒ | If greater than the specified range, test the 5 volt reference circuit for a short to voltage.

6. Ignition OFF, test for infinite resistance between the 5 volt reference circuit terminal 1 at the yaw/lat sensor and ground.

⇒ | If less than the specified value, test the 5 volt reference circuit for a short to ground.

7. Ignition OFF, test for less than 2 ohms between the 5 volt reference circuit terminal 1 at the yaw/lat sensor harness connector and terminal 23 at the EBCM harness connector.

⇒ | If greater than the specified range, test the 5 volt reference circuit for an open/high resistance.

8. Ignition ON, test for less than 1 volt between the signal circuit listed below and ground.

• | Terminal 2

• | Terminal 4

• | Terminal 5

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

9. Ignition OFF, test for infinite resistance between the signal circuit listed below and ground.

• | Terminal 2

• | Terminal 4

• | Terminal 5

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

10. Test for less than 2 ohms between the signal circuit terminals listed below.

• | Terminal 2 at the yaw sensor harness connector and terminal 37 at the EBCM harness connector.

• | Terminal 4 at the yaw sensor harness connector and terminal 16 at the EBCM harness connector.

• | Terminal 5 at the yaw sensor harness connector and terminal 38 at the EBCM harness connector.

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

11. 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 with Vehicle Lateral Accelerometer Replacement

• | Control Module References Control Module References for EBCM replacement, setup, and programming