Diagnostic Instructions

DTC Descriptors

DTC C0186 00: Lateral Accelerometer Circuit

DTC C0186 0A: Lateral Accelerometer Circuit Rate of Change Below Threshold

DTC C0186 5A: Lateral Accelerometer Circuit Plausibility Failure

DTC C0186 71: Lateral Accelerometer Circuit Invalid Serial Data Received

Diagnostic Fault Information

Circuit	Short to Ground	Open/High Resistance	Short to Voltage	Signal Performance
Lateral Accelerometer Supply Voltage Circuit	C0186	C0186	--	--
Lateral Accelerometer Communication Circuit	C0186	C0186	C0186	C0186 0A, C0186 5A, C0186 71
Lateral Accelerometer Communication Circuit	C0186	C0186	C0186	C0186 0A, C0186 5A, C0186 71
Lateral Accelerometer Communication Ground Circuit	--	C0186	--	--

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.

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

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

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1. Ignition ON, observe the scan tool Lateral Accelerometer Signal parameter. The reading should be 2.5 volts.
2. Ignition ON, observe the scan tool Yaw Rate Sensor parameter. The reading should be 2.5 volts.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the yaw rate/lateral accelerometer.
2. Test for less than 25 ohms between the ground circuit terminal 6 and ground.

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

3. Ignition ON, test for 11.8-12.2 volts between the 12-volt reference circuit terminal 1 and ground.

⇒	If less than the specified range, test the 12-volt reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the yaw rate/lateral accelerometer sensor.

4. Test for 2.2-2.8 volts between the CAN circuit terminal 4 and ground.

⇒	If greater than the specified range, test the CAN circuit for a short to voltage. If the circuit tests normal, replace the yaw rate/lateral accelerometer sensor.

⇒	If less than the specified range, test the CAN circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the yaw rate/lateral accelerometer sensor.

5. Test for 2.2-2.8 volts between the CAN circuit terminal 5 and ground.

⇒	If greater than the specified range, test the CAN circuit for a short to voltage. If the circuit tests normal, replace the yaw rate/lateral accelerometer sensor.

⇒	If less than the specified range, test the CAN circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the yaw rate/lateral accelerometer sensor.

6. Test for infinite ohm between the CAN circuit High, and Low terminals 4 and 5.

⇒	If less than the specified range, test the CAN circuits for a shorted to each other. If the circuit tests normal, replace the EBCM.

7. If all circuits test normal, test or replace the EBCM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for EBCM replacement, setup and programming