• | 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 |
---|---|---|---|---|
Yaw Rate/ Lateral Accelerometer Supply Voltage Circuit | U1826, U1827 | U1826, U1827 | U1826, U1827 | -- |
Yaw Rate/ Lateral Accelerometer Communication Circuit | U1826, U1827 | U1826, U1827 | U1826, U1827 | C0186/ C0196 09, 3B, 1A, 75, |
Yaw Rate/ Lateral Accelerometer Communication Ground Circuit | U1826, U1827 | U1826, U1827 | U1826, U1827 | -- |
The lateral accelerometer and the yaw rate sensors are combined into one sensor. The sensors communicate through the serial data network to the Vehicle Stability Control Module along with other control modules to perform stability control. The vehicle stability enhancement system (with JL7) uses the lateral accelerometer input when calculating the desired yaw rate.
The ignition is ON.
The lateral accelerometer combination changes by more than 550 meters/second per second.
The lateral accelerometer combination sensor fails an internal self test.
The lateral accelerometer combination bias exceeds 3 meters/second.
The lateral accelerometer combination signal above allowable range.
The Yaw Rate combination sensor changes by more than 455 degrees/second per second.
The Yaw Rate combination sensor fails an internal self test.
The Yaw Rate combination sensor has an internal electronic failure.
The Yaw Rate combination bias exceeds 5.7 degrees/second.
The Yaw Rate combination signal above allowable range.
• | The vehicle stability enhancement system (VSES)is disabled for the duration of the ignition cycle. |
• | The ABS/TCS remains functional. |
• | A DIC message and/or a warning indicator may be displayed. |
• | The condition for the DTC is no longer present. |
• | The EBCM automatically clears the history DTC when a current DTC is not detected in 40 consecutive drive cycles. |
Antilock Brake System Schematics
Control Module References for Scan Tool Information
Ignition ON, observe the scan tool yaw rate and lateral accelerometer sensor parameter. The reading should be the same on all sensors when driving in a straight line at a constant speed greater than 20 km/h (13 mph), and will vary as the vehicle changes direction.
⇒ | If DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle. |
⇒ | If greater than the specified range, test the low reference circuit for an open/high resistance. |
⇒ | If not within the specified range, test the ignition voltage circuit for a short to ground or open/high resistance. If DTC resets, replace the EBCM. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for EBCM replacement, setup and programming |