Diagnostic Instructions

DTC Descriptors

DTC C0186 00: Lateral Accelerometer Circuit Electrical Failure

DTC C0186 5A: Lateral Accelerometer Circuit Erratic

DTC C0186 3B: Lateral Accelerometer Self Test Failure

DTC C0186 1A: Lateral Accelerometer Offset Failure

Diagnostic Fault Information

Circuit	Short to Ground	Open/High Resistance	Short to Voltage	Signal Performance
Lateral Accelerometer Supply Voltage	C0186 00	C0186 00	--	--
Lateral Accelerometer CAN Bus High	C0186 00	C0186 00	C0186 00	C0186 5A, C0186 3B, C0186 1A
Lateral Accelerometer CAN Bus Low	C0186 00	C0186 00	C0186 00	C0186 5A, C0186 3B, C0186 1A
Lateral Accelerometer Ground	--	C0186 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 vehicle stability enhancement system (VSES) uses the lateral accelerometer input when calculating the desired yaw rate. The usable output signal is a serial data CAN circuits.

Conditions for Running the DTC

The ignition switch is in the ON position.

Conditions for Setting the DTC

Action Taken When the DTC Sets

One or more of the following actions may occur:

Conditions for Clearing the DTC

Diagnostic Aids

Possible causes of this DTC are as follows:

Reference Information

Schematic Reference

Antilock Brake System Schematics

Connector End View Reference

Antilock Brake System Connector End Views

Electrical Information Reference

Scan Tool Reference

Scan Tool Data List for EBCM

Circuit/System Verification

With scan tool installed, clear the DTCs then drive the vehicle in a straight line at a speed greater than 20 km/h (13 mph). If the DTC did not set as a current DTC see Diagnostic Aids.

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

⇒	If not within the specified range, test the ignition voltage circuit for a short to ground or open/high resistance. If the circuit tests normal, replace the EBCM.

4. Ignition OFF, disconnect the harness connector at the EBCM.
5. Ignition ON, test for less than 1 volt between the following terminal listed below and ground.

•	CAN Bus High serial data circuit terminal 18

•	CAN Bus Low serial data circuit terminal 19

⇒	If greater than the specified value, test the appropriate serial data circuit for a short to voltage. If the circuit tests normal, test or replace the vehicle yaw sensor.

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

•	CAN Bus High serial data circuit terminal 18

•	CAN Bus Low serial data circuit terminal 19

⇒	If not the specified value, test the appropriate serial data circuit for a short to ground. If the circuit tests normal, test or replace the vehicle yaw sensor.

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

•	CAN Bus High serial data circuit terminal 18 at the EBCM harness connector and terminal 2 at the yaw/lat sensor harness connector.

•	CAN Bus Low serial data circuit terminal 19 at the EBCM harness connector and terminal 1 at the yaw/lat sensor harness connector.

⇒	If greater than the specified range, test the appropriate serial data circuit for an open/high resistance. If the circuit tests normal, test or replace the vehicle yaw sensor.

8. Test for infinite resistance between the CAN Bus High serial data circuit terminal 18 and the CAN Bus Low serial data circuit terminal 19.

⇒	If not the specified value, repair the serial data circuits for a short to each other.

9. If all circuits test normal, replace the EBCM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.