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DTC C0186

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 Descriptor

DTC C0186 5A: Lateral Acceleration Sensor Plausibility Failure

DTC C0186 71: Lateral Acceleration Sensor Invalid Serial Data Received

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Ignition Voltage

C0186 71

C0186 71

—

C0186 5A, C0186 71

Low Reference

—

C0186 71

C0186 71

C0186 5A, C0186 71

CAN Bus High Serial Data

C0186 71

C0186 71

C0186 71

C0186 5A, C0186 71

CAN Bus Low Serial Data

C0186 71

C0186 71

C0186 71

C0186 5A, C0186 71

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 yaw rate/lat sensor communicates with the EBCM via discrete CAN Bus High and CAN Bus Low serial data circuits.

Conditions for Running the DTC

The ignition is ON.

Conditions for Setting the DTC
    • The yaw/lateral combination sensor reports an internal failure.
    • The yaw/lateral combination sensor learns a wrong offset value.
    • Incorrectly mounted yaw/lateral sensor.

Action Taken When the DTC Sets
    • The EBCM disables the vehicle stability enhancement system (VSES) for the duration of the ignition cycle.
    • A warning indicator on the information display module may be displayed.

Conditions for Clearing the DTC
    • The condition for the DTC is no longer present.
    • The EBCM clears the history DTC when a current DTC is not detected in 40 consecutive drive cycles.

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

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

Control Module References

Circuit/System Testing
  1. Ignition OFF, disconnect the harness connector at the yaw rate/lateral acceleration sensor.
  2. Ignition OFF, test for less than 1 ohm between the low reference circuit terminal 6 and ground.
    3. ⇒If greater than the specified range, test the low reference circuit for an open/high resistance.
  3. Ignition ON, test for ignition voltage between the ignition voltage circuit terminal 5 and ground.
    4. ⇒If not within the specified range, test the ignition voltage circuit for a short circuit to ground or open/high resistance.
  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.
    6. • CAN Bus High serial data circuit terminal 12
    • CAN Bus Low serial data circuit terminal 24
    ⇒If greater than the specified value, test the appropriate serial data circuit for a short circuit to voltage.
  6. Ignition OFF, test for infinite resistance between the following terminal listed below and ground.
    7. •  CAN Bus High serial data circuit terminal 12
    •  CAN Bus Low serial data circuit terminal 24
    ⇒If not the specified value, test the appropriate serial data circuit for a short circuit to ground.
  7. Test for less than 1 ohm between the appropriate serial data circuit terminals listed below.
    8. • CAN Bus High serial data circuit terminal 12 at the EBCM harness connector and terminal 3 at the yaw rate/lateral acceleration sensor harness connector
    • CAN Bus Low serial data circuit terminal 24 at the EBCM harness connector and terminal 1 at the yaw rate/lateral acceleration sensor harness connector
    ⇒If greater than the specified range, test the appropriate serial data circuit for an open/high resistance.
  8. Test for infinite resistance between the CAN Bus High serial data circuit terminal 12 and the CAN Bus Low serial data circuit terminal 24.
    9. ⇒If not the specified value, repair the serial data circuits for a short circuit together.
  9. If all circuits test normal, replace the yaw rate/lateral acceleration sensor. If the DTC resets, replace the EBCM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Vehicle Yaw Sensor Replacement
    •  Control Module References
   


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