Antilock Brake System - Greater than/Equal to 3900 kg (8600 lb) GVW
DTC C0186, C0196, or C0287
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.
DTC Descriptors
DTC C0186 55
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Lateral Accelerometer Circuit Expected Number of Transition/Events Exceeded
DTC C0186 5A
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Lateral Accelerometer Circuit Not Plausible
DTC C0186 0F
-
Lateral Accelerometer Circuit Erratic
DTC C0196 55
-
Yaw Rate Circuit Expected Number of Transition/Events Exceeded
DTC C0196 5A
-
Yaw Rate Circuit Not Plausible
DTC C0196 0F
-
Yaw Rate Circuit Erratic
DTC C0287 4B
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Longitudinal Acceleration Sensor Circuit Calibration Not Learned
DTC C0287 55
-
Longitudinal Acceleration Sensor Circuit Expected Number of Transition/Events Exceeded
DTC C0287 5A
-
Longitudinal Acceleration Sensor Circuit Not Plausible
DTC C0287 0F
-
Longitudinal Acceleration Sensor Circuit Erratic
Diagnostic Fault Information
Circuit/System Description
The yaw rate, lateral acceleration, and longitudinal acceleration sensors are combined into one yaw and lateral accelerometer sensor, external to the electronic brake control module. The electronic brake control module supplies a 12 V reference to the accelerometer sensor. The accelerometer sensor communicates with the electronic brake control module via serial data. The module activates the stability control and the hill start assist function depending on the information received from the yaw and lateral accelerometer sensor.
Conditions for Running the DTC
* Ignition ON.
* Ignition voltage is greater than 10 volts.
Conditions for Setting the DTC
C0186 55
* The yaw and lateral accelerometer sensor detects an internal failure.
* The lateral signal shows a value that is greater than a max value 14.715 m/s2 for 30 seconds.
* The yaw and lateral accelerometer sensor has an internal fault, the lateral signal does not change or is locked on a constant value.
C0186 5A
* A correlation error between the yaw and lateral accelerometer sensor and steering wheel angle sensor.
* Communication is lost between the electronic brake control module and the yaw and lateral accelerometer sensor.
C0186 0F, C0196 0F, or C0287 0F
* Incorrectly mounted or loose yaw and lateral accelerometer sensor.
* The yaw and lateral accelerometer sensor detects an internal failure.
C0196 55
* The yaw and lateral accelerometer sensor detects an internal failure.
* The yaw and lateral accelerometer sensor has an internal fault, the yaw rate signal does not change or is locked on a constant value.
C0196 5A
* The yaw rate has an offset greater than 5 degrees per second.
* Communication is lost between the electronic brake control module and the yaw and lateral accelerometer sensor.
* The yaw rate sensor signal is not plausible with the lateral acceleration sensor signal, steering angle sensor signal and the vehicle speed.
C0287 4B
The longitudinal acceleration sensor is not calibrated.
C0287 55
The difference between the measured longitudinal signal and the estimated longitudinal signal from wheel speed signal is greater than 1.0 m/s2 for 60 seconds.
C0287 5A
The longitudinal acceleration signal has an offset is greater than 3 m/s2.
Action Taken When the DTC Sets
One or more of the following actions may occur:
* The ABS indicator illuminates.
* The Stabilitrak indicator illuminates.
* A driver information center message and/or a warning indicator may be displayed.
* The electronic brake control module disables the antilock brake system, the traction control system, the hill start assist and the vehicle stability enhancement system for the duration of the ignition cycle.
Conditions for Clearing the DTC
* The condition for setting the DTC is no longer present.
* The history DTC will clear after 40 consecutive fault-free drive cycles have occurred.
* Operate the vehicle at speeds greater than 15 km/h (10 mph) to complete the self test, and the electronic brake control module will turn off the ABS indicator.
Diagnostic Aids
* The yaw and lateral accelerometer sensor is not calibrated.
* Incorrectly mounted or loose yaw and lateral accelerometer sensor.
Reference Information
Schematic Reference
Antilock Brake System Schematics [1][2]Antilock Brakes / Traction Control Systems
Connector End View Reference
Component Connector End Views Connector End Views By Name
Description and Operation
ABS Description and Operation Description and Operation
Electrical Information Reference
* Circuit Testing Circuit Testing
* Connector Repairs Connector Repairs
* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs Wiring Repairs
Scan Tool Reference
Control Module References Control Module References for scan tool information
Circuit/System Testing
1. Ignition ON.
2. Verify that DTC U1826, C0292, C0870 or C0710 is not set.
• If any of the DTCs are set
Refer to Diagnostic Trouble Code (DTC) List - Vehicle Diagnostic Trouble Code (DTC) List - Vehicle.
• If none of the DTC are set
3. Verify that DTC C0287 4B is not set.
• If DTC C0287 4B is set
Refer to Vehicle Yaw Sensor Learn Testing and Inspection.
• If DTC C0287 4B is not set
4. Inspect the yaw and lateral accelerometer sensor for correct installation.
• If loose or incorrect installation
Correct the installation or replace the component.
• If correct installation
5. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the yaw and lateral accelerometer sensor. It may take up to 2 minutes for all vehicle systems to power down.
6. Test for less than 5 ohms between the ground circuit terminal 1 and ground.
• If 5 ohms or greater
1. Ignition OFF.
2. Test for less than 2 ohms in the ground circuit end to end.
• If 2 ohms or greater, repair the open/high resistance in the circuit
• If less than 2 ohms, repair the open/high resistance in the ground connection.
• If less than 5 ohms
7. Ignition ON.
8. Verify a test lamp illuminates between the 12 V reference circuit terminal 4 and ground.
• If the test lamp does not illuminate
1. Ignition OFF, disconnect the harness connector at the electronic brake control module.
2. Test for infinite resistance between the 12 V reference circuit and ground.
• If less than infinite resistance, repair the short to ground on the circuit.
• If infinite resistance.
3. Test for less than 2 ohms in the 12 V reference circuit end to end.
• If 2 ohms or greater, repair the open/high resistance in the circuit.
• If less than 2 ohms, replace the electronic brake control module.
• If the test lamp illuminates
9. Replace the yaw and lateral accelerometer sensor.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the repair.
* Vehicle Yaw Sensor with Vehicle Lateral Accelerometer Replacement Service and Repair
* Control Module References Control Module References for electronic brake control module replacement, programming and setup