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 CircuitDiagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
5-Volt Reference | C0292 00 | C0292 00 | C0292 00 | -- |
Lateral Accelerometer Signal | C0186 00 | C0186 00 | C0186 00 | -- |
Low Reference | C0186 00 C0196 00 | C0186 00 C0196 00 | C0186 00 C0196 00 | -- |
Yaw Rate Sensor Signal | C0196 00 | C0196 00 | C0196 00 | -- |
Yaw Rate Frequency Signal | C0196 28 | C0196 28 | C0196 28 | C0196 28 |
Longitudinal Accelerometer Sensor Signal | -- | -- | -- | -- |
Circuit/System Description
The yaw rate/ lateral accelerometer 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 usable output voltage range for the lateral accelerometer is 0.25-4.75 volts.
Conditions for Running the DTC
Ignition voltage is greater than 9 volts.
Conditions for Setting the DTC
| • | The yaw/lateral combination sensor signal output voltage to the EBCM is less than 0.15 volt or greater than 4.85 volts. |
| • | The yaw rate/lateral accelerometer sensor fails an internal self test. |
Action Taken When the DTC Sets
If equipped, the following actions will occur:
| • | The EBCM turns OFF the 5 volt reference circuit, until the ignition is cycled. |
| • | The EBCM disables the VSES for the duration of the ignition cycle. |
| • | The driver information center (DIC) displays the Service Stability System message. |
| • | The ABS/traction control system (TCS) remains functional. |
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. |
Diagnostic Aids
| • | If the yaw rate and lateral accelerometer sensor is disconnected, DTCs will set and the EBCM will not provide 5 volt reference. |
| • | The yaw rate and lateral accelerometer sensors are located in one unit and cannot be serviced separately. |
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
Verify that DTC C0292 is not set.
| ⇒ | If DTC is set, refer to |
Circuit/System Testing
- Ignition OFF, disconnect the harness connector at the combination yaw/lateral accelerometer sensor.
- Test for less than 1 ohm between the low reference circuit terminal 6 and ground.
- Ignition ON, test for less than 1 volt between the following circuits listed below and ground.
- Ignition OFF, test for infinite resistance between the following circuits listed below and ground.
- Disconnect the harness connector at the EBCM.
- Test for less than 1 ohm between the following terminals listed below.
- If all circuits test normal, replace the EBCM.
| ⇒ | If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the EBCM. |
| • | 5-volt reference circuit terminal 1 |
| • | yaw signal circuit terminal 3 |
| • | lateral accelerometer signal circuit terminal 2 |
| • | yaw frequency circuit terminal 5 |
| ⇒ | If greater than the specified range, test the appropriate circuit for a short to voltage. If the circuit tests normal, replace the EBCM. |
| • | 5-volt reference circuit terminal 1 |
| • | yaw signal circuit terminal 3 |
| • | lateral accelerometer signal circuit terminal 2 |
| • | yaw frequency circuit terminal 5 |
| ⇒ | If less than the specified value, test the signal circuit for a short to ground. If the circuit tests normal, replace the EBCM. |
| • | 5-volt reference circuit terminal 1 and 23 |
| • | yaw signal circuit terminal 3 and 37 |
| • | lateral accelerometer signal circuit terminal 2 and 8 |
| • | yaw frequency circuit terminal 5 and 38 |
| ⇒ | If greater than the specified range, test the appropriate circuit for an open/high resistance. If the circuit test normal, replace the combination yaw/lateral accelerometer sensor. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for EBCM replacement, setup, and programming |
