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 C0196 00: Yaw Rate Circuit
DTC C0196 28: Yaw Rate Circuit Incorrect Frequency
Diagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
5 Volt Reference | C0196 00, C0196 28, C0292 00 | C0186 00, C0196 00, C0196 28 | C0292 00** | C0186 00, C0196 00, C0196 28 |
Lateral Accelerometer Signal | C0186 00 | C0186 00 | C0186 00**, C0292 00 * | -- |
Yaw Rate Signal | C0196 00 | C0196 00 | C0196 00**, C0196 28**, C0292 00* | -- |
Yaw Rate Diagnostic Signal | C0196 28 | C0196 28 | C0196 00**, C0196 28**, C0292 00* | -- |
Yaw Rate Frequency Signal | -- | -- | C0196 28 | C0196 28 |
Low Reference | -- | C0196 28 | C0196 28** | -- |
* Short to 5v ** Short to B+ | ||||
Circuit/System Description
The vehicle stability enhancement system (VSES) is activated by the electronic brake control module (EBCM) calculating the desired yaw rate and comparing it to the actual yaw rate input. The desired yaw rate is calculated from measured steering wheel position, vehicle speed, and lateral acceleration. The difference between the desired yaw rate and actual yaw rate is the yaw rate error, which is a measurement of oversteer or understeer. If the yaw rate error becomes too large, the EBCM will attempt to correct the vehicle's yaw motion by applying differential braking to the wheels.
Conditions for Running the DTC
| • | Ignition ON. |
| • | Ignition voltage is greater than 10 volts. |
Conditions for Setting the DTC
C0186 00
| • | The EBCM detects a short to voltage, short to ground or an open/high resistance in the lateral signal circuit |
| • | The EBCM detects a short to ground or an open/high resistance in the 5 volt reference circuit. |
| • | The yaw/lateral combination sensor fails an internal self test. |
C0196 00
| • | The EBCM detects a short to voltage, short to ground or an open/high resistance in the yaw rate signal circuit |
| • | The yaw/lateral combination sensor fails an internal self test. |
| • | The EBCM detects an open/high resistance in the 5 volt reference circuit |
C0196 28
| • | The EBCM detects an open/high resistance on the low reference circuit or the 5 volt reference circuit. |
| • | The EBCM detects a short to voltage in the yaw signal circuit or the yaw rate frequency signal circuit. |
| • | The EBCM detects a short to ground, open/high resistance or a short to voltage in the yaw rate diagnostic signal circuit. |
Action Taken When the DTC Sets
| • | The EBCM disables the VSES for the duration of the ignition cycle. |
| • | A DIC message and/or a warning indicator 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 100 consecutive drive cycles. |
Reference Information
Schematic Reference
Antilock Brake System Schematics
Connector End View Reference
Antilock Brake System Connector End Views
Description and Operation
Electrical Information Reference
Scan Tool Reference
Circuit/System Testing
- Ignition OFF, disconnect the harness connector at the yaw/lat sensor.
- Ignition OFF for 60 seconds, test for less than 5 ohms between the low reference circuit terminal 6 and ground.
- Ignition OFF, disconnect the harness connector at the EBCM.
- Ignition ON, test for less than 1 volt between the 5 volt reference circuit terminal 1 and ground at the yaw/lat sensor.
- Ignition OFF, test for infinite resistance between the 5 volt reference circuit terminal 1 and ground.
- Ignition OFF, test for less than 2 ohms between the 5 volt reference circuit terminal 1 at the yaw/lat sensor harness connector and terminal 23 at the EBCM harness connector.
- Ignition ON, test for less than 1 volt between the signal circuit listed below and ground.
- Ignition OFF, test for infinite resistance between the signal circuit listed below and ground.
- Test for less than 2 ohms between the signal circuit terminals listed below.
- If all circuits test normal, replace the yaw/lat sensor. If the DTC resets, 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. |
| ⇒ | If greater than the specified range, test the 5 volt reference circuit for a short to voltage. |
| ⇒ | If less than the specified value, test the 5 volt reference circuit for a short to ground. |
| ⇒ | If greater than the specified range, test the 5 volt reference circuit for an open/high resistance. |
| • | Lateral accelerometer terminal 2 |
| • | Yaw rate sensor terminal 3 |
| • | Yaw rate diagnostic terminal 4 |
| • | Yaw rate frequency terminal 5 |
| ⇒ | If greater than the specified range, test the signal circuit for a short to voltage. |
| • | Lateral accelerometer terminal 2 |
| • | Yaw rate sensor terminal 3 |
| • | Yaw rate diagnostic terminal 4 |
| • | Yaw rate frequency terminal 5 |
| ⇒ | If less than the specified value, test the signal circuit for a short to ground. |
| • | Lateral accelerometer terminal 2 at the yaw sensor harness connector and terminal 8 at the EBCM harness connector. |
| • | Yaw rate sensor terminal 3 at the yaw sensor harness connector and terminal 37 at the EBCM harness connector. |
| • | Yaw rate diagnostic terminal 4 at the yaw sensor harness connector and terminal 9 at the EBCM harness connector. |
| • | Yaw rate frequency terminal 5 at the yaw sensor harness connector and terminal 38 at the EBCM harness connector. |
| ⇒ | If greater than the specified range, test the signal circuit for an open/high resistance. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Vehicle Yaw Sensor with Vehicle Lateral Accelerometer ReplacementVehicle Yaw Sensor with Vehicle Lateral Accelerometer Replacement |
| • | Control Module ReferencesControl Module References for EBCM replacement, setup, and programming |
