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 00: Lateral Accelerometer CircuitDTC C0186 08: Lateral Accelerometer Circuit Signal Invalid
DTC C0186 09: Lateral Accelerometer Circuit Rate of Change Above Threshold
DTC C0186 19: Lateral Accelerometer Circuit Signal Amplitude Above Maximum
DTC C0186 1A: Lateral Accelerometer Circuit Bias Level Out Of Range
DTC C0186 52: Lateral Accelerometer Circuit Compare Failure
Diagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
Lateral Accelerometer 5 volt Reference Circuit | C0186 00 | C0186 00 | C0186 00, C0186 19 | -- |
Lateral Accelerometer Signal Circuit | C0186 00 | C0186 00 | C0186 00, C0186 08, C0186 09, C0186 19 | C0186 1A, C0186 08, C0186 09, C0186 52 |
Lateral Accelerometer Low Reference Circuit | -- | C0186 00 | -- | -- |
Circuit/System Description
The electronic brake control module (EBCM) uses the lateral accelerometer signal to determine the lateral forces acting on a vehicle during a turn or a skid. The EBCM uses the signal from the lateral accelerometer as one of the inputs to operate the vehicle stability enhancement system (VSES).
Conditions for Running the DTC
C0186 00, 09, and 1A
| • | The ignition is ON. |
| • | Ignition voltage is greater than 8 volts. |
C0186 08
| • | Ignition voltage is ON. |
| • | Ignition voltage is greater than 8 volts. |
| • | The vehicle speed is greater than 0 km/h. |
C0186 19
| • | Ignition voltage is ON. |
| • | Ignition voltage is greater than 8 volts. |
| • | The vehicle is stationary. |
C0186 52
| • | Ignition voltage is ON. |
| • | Ignition voltage is greater than 8 volts. |
| • | DTC C0196 is not set. |
| • | The yaw rate is less than 8 degrees per second. |
Conditions for Setting the DTC
C0186 00, 09, and 1A
One of the following conditions exist:
| • | The lateral accelerometer sensor input voltage is less than 0.15 volt. |
| • | The lateral accelerometer sensor input voltage is greater than 4.85 volts for 0.03 second. |
C0186 08
The lateral accelerometer signal voltage does not increase 0.5 volt during the lateral accelerometer sensor self test.
C0186 09
The lateral accelerometer signal exceeds 108 m/s² (11 g) per second twice within 0.2 second.
C0186 19
The lateral accelerometer signal is greater than 4.9 m/s² (0.5 g) for 1 second.
C0186 1A
Both of the following conditions exist:
| • | The compensated bias value of the lateral accelerometer sensor is greater than 2.9 m/s² (0.3 g). |
| • | The yaw rate is centered. |
C0186 52
The slip rate error is greater than 4.9 m/s² (0.5 g) 60 times within one drive cycle.
Action Taken When the DTC Sets
If equipped, the following actions will occur:
| • | The EBCM disables the VSES for the duration of the ignition cycle. |
| • | The vehicle dynamics caution (VDC) indicator illuminates. |
| • | The driver information center (DIC) displays the SERVICE STABILITRAK message. |
| • | The antilock brake system (ABS) and the traction control system (TCS) remain functional. |
Conditions for Clearing the DTC
| • | The condition for the DTC is no longer present and the DTC is cleared with a scan tool. |
| • | The EBCM automatically clears the history DTC when a current DTC is not detected in 100 consecutive drive cycles. |
Diagnostic Aids
The lateral accelerometer is packaged with the yaw rate sensor as a single component.
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 Testing
- Ignition OFF, disconnect the harness connector at the yaw and lateral/long acceleration sensor.
- Test for less than 5 ohms of resistance between the low reference circuit terminal D and ground.
- Ignition ON, test for 4.8-5.2 volts between the 5 volt reference circuit terminal B and ground.
- Verify the scan tool Lateral Accelerometer Signal parameter is less than 0 volts.
- Install a 3 A fused jumper wire between the signal circuit terminal E and the 5 volt reference circuit terminal B. Verify the scan tool Lateral Accelerometer Signal is greater than 4.8 volts.
- If all circuits test normal, test or replace the yaw and lateral/long acceleration sensor.
| ⇒ | 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 less than the specified range, test the 5 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 5 volt reference circuit for a short to voltage. If the circuit tests normal, replace the EBCM. |
| ⇒ | If greater than the specified range, test the signal circuit terminal E for a short to voltage. If the circuit tests normal, replace the EBCM. |
| ⇒ | If less than the specified range, test the signal circuit for a short to voltage or an open/high resistance. 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 |
