TCS or ASC

DTC U0100: Engine time-out error
DTC U0101: TC-SST time-out error
DTC U0126: Steering wheel sensor time-out error
DTC U0141: ETACS time-out error
DTC U0136: AWC 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.
^ If diagnostic trouble codes U0100, U0101, U0126, U0141, and U0136 are set in ASC-ECU, always diagnose CAN bus lines. If there is any fault in the CAN bus lines, an incorrect DTC may be set.
^ Whenever the ECU is replaced, ensure that the CAN bus lines are normal.
^ When the steering wheel sensor is replaced, always perform calibration to make ASC-ECU learn the neutral point.
^ When the hydraulic unit (integrated with ASC-ECU) is replaced, after turning the ignition switch ON and OFF (vehicle information from ETACS-ECU is registered), always perform the calibration of steering wheel sensor, G and yaw rate sensor, brake fluid pressure sensor, cut valve, and inlet valve.

CIRCUIT OPERATION
ASC-ECU communicates with the engine control module, TC-SST-ECU, steering wheel sensor, ETACS-ECU, and AWC-ECU via the CAN bus lines.

DTC SET CONDITIONS
The diagnostic trouble code is stored if ASC-ECU cannot receive the signal sent from other ECU for a specified period.

PROBABLE CAUSES

DTC U0100
^ Wring harness or connector failure of CAN bus line
^ Engine ECU malfunction
^ ASC-ECU malfunction

DTC U0101
^ Wring harness or connector failure of CAN bus line
^ Malfunction of TC-SST-ECU
^ ASC-ECU malfunction
^ Interchanging of ETACS-ECU

DTC U0126
^ Damaged wiring harness or connector in CAN bus line
^ Malfunction of steering wheel sensor
^ Malfunction of ASC-ECU

DTC U0141
^ Wring harness or connector failure of CAN bus line
^ Malfunction of ETACS-ECU
^ ASC-ECU malfunction

DTC U0136
^ Wring harness or connector failure of CAN bus line
^ AWC-ECU malfunction
^ ASC-ECU malfunction

DIAGNOSIS

Required Special Tools:
^ MB991958 Scan Tool (M.U.T.-III Sub Assembly)
^ MB991824: Vehicle Communication Interface (V.C.I.)
^ MB991827 M.U.T.-III USB Cable
^ MB991910 M.U.T.-III Main Harness A

STEP 1. Using scan tool MB991958, diagnose the CAN bus lines.
Using scan tool MB991958, diagnose the CAN bus lines.
Q: Is the check result normal?
YES: Go to Step 2.
NO: Repair the CAN bus lines. (Refer to Troubleshooting Can Bus Diagnostics Table.) After repairing the CAN bus line, go to Step 5.

STEP 2. Scan tool diagnostic trouble code for other systems
Using scan tool MB991958, check if any other diagnostic trouble code is set in the ECU corresponding to the relevant diagnosis.
Q: Is other DTC set?
YES: Perform troubleshooting for the diagnostic trouble code that is set.
NO: Go to Step 3.

STEP 3. Using scan tool MB991958, check read the DTC other system.
Use scan tool to check if the same DTC (time-out) is set in the other ECU (CAN-C).
Q: Is any DTC set?
YES (DTC U0100 is set): Replace the engine control module (ECM), and then go to Step 4.
YES (DTC U0101 is set): Replace the TC-SST-ECU, and then go to Step 4.
YES (DTC U0126 is set): Replace steering wheel sensor, and then go to Step 4.
YES (DTC U0141 is set): Replace the ETACS-ECU, and then go to Step 4.
YES (DTC U0136 is set): Replace the AWC-ECU, and then go to Step 4.
NO (No DTC is set.): The procedure is complete.

STEP 4. Check whether the DTC is reset.
Q: Is DTC U0100, U0101, U0126, U0141 or U0136 set?
YES: Replace the hydraulic unit (incorporates in ASC-ECU). Then go to Step 5.
NO: Intermittent malfunction.

STEP 5. Check whether the DTC is reset.
Q: Is DTC U0100, U0101, U0126, U0141 or U0136 set?
YES: Return to Step 1.
NO: The procedure is complete.