Active Stability Control System (ASC)

DTC U0100: Engine time-out error
DTC U0101: CVT time-out error
DTC U0114: AWD time-out error
DTC U0126: Steering wheel sensor time-out error
DTC U0141: ETACS time-out error

CAUTION:

- If there is any problem in the CAN bus lines, an incorrect diagnostic trouble code may be set. Prior to this diagnosis, diagnose the CAN bus lines CAN Bus Line Diagnostics Flow ).
- If diagnostic trouble codes U0100, U0101, U0114, U0126, and U0141 are set in ASC-ECU, always diagnose the CAN bus line. If there is any fault in the CAN bus lines, an incorrect diagnostic trouble code may be set. In this case, the set diagnostic trouble code is not highly reliable.
- Before replacing the ECU, ensure that the communication circuit is normal.
- When the steering wheel sensor is replaced, always carry out calibration to make ASC-ECU learn the neutral point (Refer to Testing and Inspection ).
- When the hydraulic unit (integrated with ASC-ECU) is replaced, always carry out the calibration of the steering wheel sensor, the G and yaw rate sensor and brake fluid pressure sensor (Refer to Testing and Inspection , Testing and Inspection and Testing and Inspection ).

CIRCUIT OPERATION

ASC-ECU communicates with the engine control module, TCM, AWD-ECU, the steering wheel sensor, and ETACS-ECU via the CAN bus lines.

DTC SET CONDITIONS

This diagnostic trouble code is set if ASC-ECU cannot receive the signal sent from other ECU for a certain period.

PROBABLE CAUSES

DTC U0100

- Wiring harness or connector failure of CAN bus line
- Engine control module malfunction
- ASC-ECU malfunction
- Connector disconnected or improperly connected
- Stretched or broken wires

DTC U0101

- Wiring harness or connector failure of CAN bus line
- Malfunction of TCM
- ASC-ECU malfunction
- Connector disconnected or improperly connected
- Stretched or broken wires

DTC U0114

- Wiring harness or connector failure of CAN bus line
- AWD-ECU malfunction
- ASC-ECU malfunction
- Connector disconnected or improperly connected
- Stretched or broken wires

DTC U0126

- Wiring harness or connector failure of CAN bus line
- Steering wheel sensor malfunction
- ASC-ECU malfunction
- Connector disconnected or improperly connected
- Stretched or broken wires

DTC U0141

- Wiring harness or connector failure of CAN bus line
- Malfunction of ETACS-ECU
- ASC-ECU malfunction
- Connector disconnected or improperly connected
- Stretched or broken wires

DIAGNOSIS

STEP 1. Using scan tool MB991958, diagnose the CAN bus line.

Use scan tool MB991958 to diagnose the CAN bus lines.

Q. Is the check result normal?

YES Go to Step 2.
NO Repair the CAN bus lines CAN Bus Diagnostics Chart).
On completion, go to Step 3.
STEP 2. Check whether the DTC is reset.

Q. Is DTC U0100, U0101, U0114, U0126 or U0141 set?

YES Go to Step 3.
NO The procedure is complete.
STEP 3. Connector check: ASC-ECU connector

Q. Is the check result normal?

YES Go to Step 4.
NO Repair the defective connector. Then go to Step 4.
STEP 4. M.U.T.-III other system DTC

Use scan tool to check that other diagnostic trouble code is set in the ECU corresponding to the relevant diagnosis.

Q. Is other DTC set?

YES Troubleshoot for the relevant diagnostic trouble code.
NO Go to Step 5.
STEP 5. ETACS-ECU coding data check

Programming and Relearning.

Q. Is the check result normal?

YES Go to Step 6.
NO Replace the ETACS-ECU Electronic Time and Alarm Control System (ETACS)-ECU Removal and Installation), and then go to Step 6.
STEP 6. Check whether the DTC is reset.

Erase the DTCs.

Q. Is DTC U0100, U0101, U0114, U0126 or U0141 set?

YES Replace the hydraulic unit (integrated with ASC-ECU) (Refer to Service and Repair).
NO The procedure is complete.