• | 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. |
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
---|---|---|---|---|
5-Volt Reference | C0196 00 | C0196 00 | C0196 00 | C0196 09, C0196 1A, C0196 52 |
Lateral Accelerometer Signal | C0186 00, C0186 08 | C0186 00, C0186 08 | C0186 00, C0186 08 | C0186 09, C0186 1A, C0186 19, C0186 52 |
Yaw Rate Signal | C0196 00 | C0196 00 | C0196 00 | C0196 09, C0196 1A, C0196 52 |
Low Reference | C0186 00, C0196 00 | C0186 00, C0196 00 | C0186 00, C0196 00 | -- |
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 and yaw rate input to identify when the vehicle is in an abrupt maneuver.
• | The ignition voltage is greater than 9.6 volts. |
• | The vehicle is stopped or the vehicle speed is greater than 45 km/h (28 mph). |
One of the following conditions exist:
• | The yaw/lateral combination sensor signal output voltage to the EBCM is less than 0.15 volt or greater than 4.85 volts. |
• | The vehicle speed has reached at least 15 km/h (9 mph) from a stop more three times during the same ignition cycle. During the time the vehicle is stationary, the yaw rate signal value is more than 7 deg/sec for 2 seconds. |
• | When vehicle speed is more than 25 km/h (16 mph) in a turn the difference between the yaw rate, steering angle, lateral acceleration, and wheel speed sensor values are not correlated three consecutive times. |
• | Yaw rate changes greater than 20 deg/sec in 6 ms four times in one second. |
• | The yaw/lateral combination sensor fails an internal self test. |
• | The EBCM disables the VSES for the duration of the ignition cycle. |
• | A DIC message and/or a warning indicator may be displayed. |
• | 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. |
Antilock Brake System Schematics
Control Module References for scan tool information
⇒ | 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 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 ground or an open/high resistance. If the circuit tests normal, replace the EBCM. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for EBCM replacement, setup, and programming |
• | 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. |
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
---|---|---|---|---|
5-Volt Reference | 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** | C0186 00 |
Longitudinal Signal | C0196 28 | C0196 28 | C0196 28 | -- |
Yaw Rate Signal | C0196 00 | C0196 00 | C0196 00*, C0196 28*, C0292 00** | C0186 00, C0196 00 |
Low Reference | -- | C0196 28 | -- | -- |
* Short to 5v ** Short to B+ |
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.
• | The ignition voltage is greater than 9.6 volts. |
• | The vehicle is stopped or the vehicle speed is greater than 45 km/h (28 mph). |
• | The EBCM detects an open or short to ground in the yaw signal circuit |
• | The EBCM detects an open in the 5v ref circuit |
• | The EBCM detects an open in the 5v reference circuit, or low reference circuit. |
• | The EBCM detects an open, short to ground or a short to 5 volts in the yaw signal circuit. |
• | The EBCM detects an open, short to ground, short to 5 volts, or short to B+ in the longitudinal signal circuit |
• | The EBCM detects a short to ground or a short to B+ in the 5v ref circuit. |
• | The EBCM detects a short to B+ in the yaw signal circuit or the lateral accelerometer signal circuit. |
• | The EBCM disables the VSES for the duration of the ignition cycle. |
• | A DIC message and/or a warning indicator may be displayed. |
• | 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. |
Antilock Brake System Schematics
Control Module References for scan tool information
⇒ | 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. |
• | Lateral accelerometer terminal 2 |
• | Longitudinal accelerometer terminal 5 |
• | Yaw rate terminal 3 |
⇒ | If greater than the specified range, test the signal circuit for a short to voltage. |
• | Lateral accelerometer terminal 2 |
• | Longitudinal accelerometer terminal 5 |
• | Yaw rate terminal 3 |
⇒ | 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. |
• | Longitudinal accelerometer terminal 5 at the yaw sensor harness connector and terminal 38 at the EBCM harness connector. |
• | Yaw rate terminal 3 at the yaw sensor harness connector and terminal 37 at the EBCM harness connector. |
⇒ | If greater than the specified range, test the signal circuit for an open/high resistance. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for EBCM replacement, setup, and programming |