Code No. U0101: TC-SST-ECU Time-out



caution If diagnosis code U0101 is set from engine-ECU, surely perform CAN busline diagnosis.
caution Replace ECU after certainly confirming that the communication circuits are normal.

TROUBLE JUDGMENT


Check Conditions
  • More than 2 seconds have passed since the ignition switch was turned to "ON" position.
  • Battery positive voltage is more than 10 V.
Judgement Criterion
  • Unable to receive TC-SST-ECU signals through the CAN bus line for 4 seconds.

COMMENTS ON TROUBLE SYMPTOM


Current malfunction
  • The failure is possibly caused by malfunction of the harness and connector in CAN busline between engine-ECU and TC-SST-ECU, by malfunction in the power supply system of TC-SST-ECU, in TC-SST-ECU itself, in engine-ECU.
Past malfunction
  • Proceed with troubleshooting focusing on malfunction of the harness and connector in CAN busline between engine-ECU and TC-SST-ECU and malfunction in the power supply system of TC-SST-ECU. For diagnosis procedure, refer to how to cope with past malfunctions. (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Treat Past Trouble ).
    note In the case of past malfunctions, M.U.T.-III CAN busline diagnosis cannot detect a malfunction even if there is a malfunction in CAN bus. Therefore, check CAN busline as in the case of response to intermittent malfunctions (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ). It is possible to narrow down areas with a high possibility of malfunctions from diagnosis codes set to each ECU that performs CAN communication (Refer to GROUP 54C - Explanation about the M.U.T.-III CAN Bus Diagnostics ).
FAIL-SAFE AND BACKUP FUNCTION
  • None.

PROBABLE CAUSES



  • Failed harness and connector
  • Failed TC-SST-ECU
  • Failed engine-ECU

DIAGNOSIS PROCEDURE


STEP 1. M.U.T.-III CAN bus diagnosis



  • Use M.U.T.-III to perform CAN busline diagnosis.

Q. Is the check result normal?

Go to Step 2.
Repair CAN busline (Refer to GROUP 54C - Troubleshooting - CAN Bus Diagnostics Table ). After repairing CAN busline, go to Step 6.

STEP 2. M.U.T.-III diagnosis code



  • Confirm the diagnosis code is set from the TC-SST-ECU.

Q. Is diagnosis code set?

Perform troubleshooting of TC-SST system (Refer to GROUP 22E - Diagnosis Troubleshooting <TC-SST> - Diagnosis Code Chart ).
Go to Step 3.

STEP 3. M.U.T.-III diagnosis code


Diagnosis code No. U0101 from the following ECU that performs CAN communication with TC-SST-ECU: Confirm TC-SST-ECU Time-out is set.

  • Shift lever
  • AWC-ECU
  • ASC-ECU
  • AFS-ECU
  • ETACS-ECU

Q. Is diagnosis code set?

Go to Step 4.
Go to Step 5.

STEP 4. M.U.T.-III diagnosis code



  • Reconfirmation of diagnosis code.
Confirm again the diagnosis code is set from the engine-ECU.

  1. Erase the set diagnosis code.
  2. Ignition switch: LOCK (OFF) → ON
  3. Confirm whether the diagnosis code is set.

Q. Is diagnosis code set?

After replacing TC-SST-ECU, go to Step 6.
Intermittent malfunction in CAN busline between engine-ECU and TC-SST-ECU (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).

STEP 5. M.U.T.-III diagnosis code



  • Reconfirmation of diagnosis code.
Confirm again the diagnosis code is set from the engine-ECU.

  1. Erase the set diagnosis code.
  2. Ignition switch: LOCK (OFF) → ON
  3. Confirm whether the diagnosis code is set.

Q. Is diagnosis code set?

Replace engine-ECU, go to Step 6.
Intermittent malfunction in CAN busline between engine-ECU and TC-SST-ECU (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunctions ).

STEP 6. M.U.T.-III diagnosis code



  • Reconfirmation of diagnosis code.
Confirm again the diagnosis code is set from the engine-ECU.

  1. Erase the set diagnosis code.
  2. Ignition switch: LOCK (OFF) → ON
  3. Confirm whether the diagnosis code is set.

Q. Is diagnosis code set?

Go to Step 1.
Check end.