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 CircuitDTC C0186 5A: Lateral Accelerometer Circuit Plausibility Failure
Diagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
Lateral Accelerometer Supply Voltage Circuit | C0186 00 | C0186 00 | -- | -- |
Lateral Accelerometer Communication High Circuit | C0186 00 | C0186 00 | C0186 00 | C0186 5A |
Lateral Accelerometer Communication Low Circuit | C0186 00 | C0186 00 | C0186 00 | C0186 5A |
Lateral Accelerometer Communication Ground Circuit | -- | 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.
Conditions for Running the DTC
The ignition switch is in the ON position.
Conditions for Setting the DTC
| • | The yaw/lateral combination sensor fails an internal self test. |
| • | Communication is lost between the EBCM and the yaw/lateral combination sensor. |
Action Taken When the DTC Sets
One or more of the following actions may occur:
| • | The vehicle stability enhancement system (VSES) is disabled. |
| • | Traction control system (TCS) is disabled. |
| • | The TCS/VSES indicators turn ON. |
| • | The driver information center (DIC) displays the Service Traction Control, and or Service StabiliTrak message. |
Conditions for Clearing the DTC
| • | The condition for the DTC is no longer present. |
| • | The EBCM automatically 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
Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for Scan Tool Information
Circuit/System Verification
- Ignition ON, observe the scan tool Lateral Accelerometer Signal parameter. The reading should be 2.3-2.7 volts.
- Ignition ON, observe the scan tool Yaw Rate Sensor parameter. The reading should be 2.3-2.7 volts.
Circuit/System Testing
- Ignition OFF, disconnect the harness connector at the yaw rate/lateral accelerometer.
- Test for less than 2 ohms of resistance between the ground circuit terminal 1 and ground.
- Ignition ON, test for 11.8 - 12.2 volts between the 12-volt reference circuit terminal 4 and ground.
- Test for 5.5-7.0 volts between the CAN circuit terminal 3 and ground.
- Test for 5.5-7.0 volts between the CAN circuit terminal 2 and ground.
- Test for infinite ohm of resistance between the CAN circuit High, and Low terminals 2 and 3.
- If all circuits test normal, test or replace the yaw rate/lateral accelerometer sensor.
| ⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. |
| ⇒ | 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 EBCM. |
| ⇒ | If greater than the specified range, test the CAN circuit for a short to voltage. If the circuit tests normal, replace the EBCM. |
| ⇒ | 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 EBCM. |
| ⇒ | If greater than the specified range, test the CAN circuit for a short to voltage. If the circuit tests normal, replace the EBCM. |
| ⇒ | 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 EBCM. |
| ⇒ | If less than the specified range, test the CAN circuits for a shorted to each other. If the circuit tests normal, replace the EBCM. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for EBCM replacement, setup and programming
