• | 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 |
---|---|---|---|---|
12 V Reference | U0125, U0126 | U0125, U0126 | -- | -- |
CAN Bus High Serial Data | U0073, U0074, U0100, U0101, U0104, U0125, U0126, U0128, U0136, U0139, U0140 | U0073, U0074, U0100, U0101, U0104, U0125, U0126, U0128, U0136, U0139, U0140 | U0073, U0074, U0100, U0101, U0104, U0125, U0126, U0128, U0136, U0139, U0140 | C0187 5A, C0196 5A, C019B 5A, C0287 5A |
CAN Bus Low Serial Data | U0073, U0074, U0100, U0101, U0104, U0125, U0126, U0128, U0136, U0139, U0140 | U0073, U0074, U0100, U0101, U0104, U0125, U0126, U0128, U0136, U0139, U0140 | U0073, U0074, U0100, U0101, U0104, U0125, U0126, U0128, U0136, U0139, U0140 | C0187 5A, C0196 5A, C019B 5A, C0287 5A |
Ground | -- | U0125 | -- | -- |
The yaw rate, lateral acceleration and longitudinal acceleration sensors are combined into one multi-axis sensor, external to the electronic brake control module (EBCM). The EBCM supplies a 12 V reference voltage to the multi-axis sensor. The multi-axis sensor communicates with the EBCM via the high speed controller area network (CAN) serial data circuit. The EBCM activates the stability control function depending on multi-axis sensor input.
Ignition ON
• | No lateral acceleration sensor signal |
• | The lateral acceleration sensor signal is not plausible with the yaw rate sensor signal, steering angle sensor signal and vehicle speed. |
• | The lateral acceleration sensor offset is out of specified range. |
• | No yaw rate sensor signal |
• | The yaw rate sensor signal is not plausible with the lateral acceleration sensor signal, steering angle sensor signal and vehicle speed. |
• | The yaw rate sensor offset is out of specified range. |
The yaw rate sensor signal is out of specified range.
• | No longitudinal acceleration sensor signal |
• | The longitudinal acceleration sensor signal is not plausible with the vehicle acceleration. |
• | The longitudinal acceleration sensor offset is out of specified range. |
A wrong multi-axis sensor is installed.
• | The EBCM disables the stability control and hill start assist for the duration of the ignition cycle. |
• | The traction control/stability control-active indicator turns ON. |
The EBCM disables the hill start assist for the duration of the ignition cycle.
• | A current DTC clears when the diagnostic runs and passes. |
• | The EBCM will turn OFF the indicator in the next ignition cycle. |
Antilock Brake System Schematics
Control Module References for scan tool information
Ignition ON, observe the scan tool Lateral Acceleration Signal and Yaw Rate Sensor parameters. On a level surface, the readings should be 0 V.
If vehicle is equipped with hill start assist:
Observe the scan tool Acceleration Sensor Longitudinal Signal parameter. On a level surface, the reading should be 0 V.
⇒ | If any listed DTC is present, perform the LINK X Yaw Rate Sensor Learn. |
⇒ | If greater than the specified value, test the ground circuit for an open/high resistance. |
⇒ | If less than the specified value, test the 12 V reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K17 Electronic Brake Control Module (EBCM). |
⇒ | If the DTC resets, replace the K17 Electronic Brake Control Module (EBCM). |
• | Perform the Diagnostic Repair Verification after completing the diagnostic procedure. |
• | Control Module References for EBCM replacement, setup and programming |