C0186

DTC C0186

Circuit Description

The vehicle stability enhancement system (VSES) uses the lateral accelerometer input when calculating the desired yaw rate. The usable output voltage range for the lateral accelerometer is 0.25-4.75 volts.

The lateral accelerometer sensor bias compensates for sensor mounting alignment errors and electronic signal errors.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC C0186 Lateral Accelerometer Circuit

Conditions for Running the DTC

* The ignition is ON.
* The vehicle speed is greater than 40 km/h (25 mph).

Conditions for Setting the DTC

Voltage at the lateral accelerometer signal output to the electronic brake control module (EBCM) falls outside the 0.25-4.75 volt range for more than 100 milliseconds.

Action Taken When the DTC Sets

If equipped, the following actions occur:

* The EBCM disables the traction control system (TCS)/VSES for the duration of the ignition cycle.
* A malfunction DTC is set.
* The antilock brake system (ABS) indicator turns ON.

Conditions for Clearing the DTC

* The condition for the DTC is no longer present.
* A history DTC will clear after 100 consecutive ignition cycles if the condition for the malfunction is no longer present.
* Using a scan tool

Diagnostic Aids

* A thorough inspection of the wiring system and connectors be performed. Failure to carefully and fully inspect the wiring system and connectors may result in misdiagnosis which may result in replacing good parts and the reappearance of the malfunction.
* Inspection for poor connections, broken insulation, or a wire that is broken inside the insulation.
* If an intermittent malfunction exists, refer to Testing for Intermittent Conditions and Poor Connections in Diagnostic Aids. Component Tests and General Diagnostics

Test Description

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

2. This step tests for specified voltage on the lateral accelerometer signal circuit.
3. This step tests for B+ voltage on yaw/lateral accelerometer sensor.
4. This step tests the ignition circuit for a high resistance or open.
5. This step checks to see if the voltage was below or above the specified voltage.
6. This step checks to see if the voltage was above the specified voltage.
7. This step checks to see if the voltage was below the specified voltage.
8. This step checks to see if the voltage was above the specified voltage.
9. This step checks to see if the resistance of the ground circuit is less than 5 ohms.
10. This step tests for a short to voltage on the 5-volt reference circuit.
11. This step tests for a short to ground, a high resistance, or an open in the 5-volt reference circuit.
12. This step tests for a short to ground, a high resistance, or an open in the lateral accelerometer signal circuit.
13. This step tests for a short to voltage in the lateral accelerometer signal circuit.
14. This step tests for a high resistance or an open in the ground circuit.
15. This step checks the yaw/lateral accelerometer sensor connector for poor connections.
16. This step checks the EBCM connector for poor connections.

Step 1 - Step 11:

Step 12 - Step 19: