Diagnostic Instructions

DTC Descriptor

DTC C0186 00: Lateral Accelerometer Circuit

DTC C0186 08: Lateral Accelerometer Circuit Signal Invalid

DTC C0186 09: Lateral Accelerometer Circuit Rate of Change Above Threshold

DTC C0186 19: Lateral Accelerometer Circuit Signal Amplitude Above Maximum

DTC C0186 1A: Lateral Accelerometer Circuit Bias Level Out Of Range

DTC C0186 52: Lateral Accelerometer Circuit Compare Failure

Diagnostic Fault Information

Circuit	Short to Ground	Open/High Resistance	Short to Voltage	Signal Performance
Lateral Accelerometer 5 volt Reference Circuit	C0186 00	C0186 00	C0186 00, C0186 19	--
Lateral Accelerometer Signal Circuit	C0186 00	C0186 00	C0186 00, C0186 08, C0186 09, C0186 19	C0186 1A, C0186 08, C0186 09, C0186 52
Lateral Accelerometer Low Reference Circuit	--	C0186 00	--	--

Circuit/System Description

The electronic brake control module (EBCM) uses the lateral accelerometer signal to determine the lateral forces acting on a vehicle during a turn or a skid. The EBCM uses the signal from the lateral accelerometer as one of the inputs to operate the vehicle stability enhancement system (VSES).

Conditions for Running the DTC

C0186 00, 09, and 1A

C0186 08

C0186 19

C0186 52

Conditions for Setting the DTC

C0186 00, 09, and 1A

One of the following conditions exist:

C0186 08

The lateral accelerometer signal voltage does not increase 0.5 volt during the lateral accelerometer sensor self test.

C0186 09

The lateral accelerometer signal exceeds 108 m/s² (11 g) per second twice within 0.2 second.

C0186 19

The lateral accelerometer signal is greater than 4.9 m/s² (0.5 g) for 1 second.

C0186 1A

Both of the following conditions exist:

C0186 52

The slip rate error is greater than 4.9 m/s² (0.5 g) 60 times within one drive cycle.

Action Taken When the DTC Sets

If equipped, the following actions will occur:

Conditions for Clearing the DTC

Diagnostic Aids

The lateral accelerometer is packaged with the yaw rate sensor as a single component.

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 Testing

1. Ignition OFF, disconnect the harness connector at the yaw and lateral/long acceleration sensor.
2. Test for less than 5 ohms of resistance between the low reference circuit terminal D 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 4.8-5.2 volts between the 5 volt reference circuit terminal B and ground.

⇒	If less than the specified range, test the 5 volt reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the EBCM.

⇒	If greater than the specified range, test the 5 volt reference circuit for a short to voltage. If the circuit tests normal, replace the EBCM.

4. Verify the scan tool Lateral Accelerometer Signal parameter is less than 0 volts.

⇒	If greater than the specified range, test the signal circuit terminal E for a short to voltage. If the circuit tests normal, replace the EBCM.

5. Install a 3 A fused jumper wire between the signal circuit terminal E and the 5 volt reference circuit terminal B. Verify the scan tool Lateral Accelerometer Signal is greater than 4.8 volts.

⇒	If less than the specified range, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the EBCM.

6. If all circuits test normal, test or replace the yaw and lateral/long acceleration sensor.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.