Code No. U0101: T/M CAN Timeout



caution
  • If there is any problem in the CAN bus lines, an incorrect diagnosis code may be set. Prior to this diagnosis, diagnose the CAN bus lines (Refer to GROUP 54C - Troubleshooting ).
  • If diagnosis code No. U0101 is set in ACC/FCM-ECU, always diagnose the CAN bus line. If there is any fault in the CAN bus lines, an incorrect diagnosis code may be set. In this case, the set diagnosis code is not highly reliable.
  • Whenever the ECU is replaced, ensure that the CAN bus lines are normal.
  • When the ACC/FCM-ECU is replaced, calibrate the radar (refer to ).

OPERATION


The ACC/FCM-ECU communicates with the A/T-ECU via the CAN bus lines.

DIAGNOSIS CODE SET CONDITION


The ACC/FCM-ECU receives the A/T system-related signals from the A/T-ECU via the CAN bus lines. When these signals cannot be received, the ECU sets this diagnosis code.

PROBABLE CAUSES




DIAGNOSIS PROCEDURE


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


Use M.U.T.-III to perform the CAN bus diagnosis.

Q. Is the check result normal?

Go to Step 2.
Repair the CAN bus lines (Refer to GROUP 54C - Troubleshooting ). On completion, go to Step 2.

STEP 2. Use M.U.T.-III to confirm a diagnosis code of other systems.


Check if the diagnosis code is set in the A/T-ECU (Refer to GROUP 23A - Troubleshooting <A/T>, Diagnosis Function).

Q. Is the diagnosis code set?

Troubleshoot the A/T-ECU diagnosis code (Refer to GROUP 23A - Troubleshooting <A/T>, Diagnosis Code Chart).
Go to Step 3.

STEP 3. Use M.U.T.-III to confirm a diagnosis code of other systems.


Check whether an A/T "time-out" related diagnosis code is set in other ECUs.

Q. Is the diagnosis code set?

Replace the A/T-ECU (Refer to GROUP 23A - A/T-ECU).
Go to Step 4.

STEP 4. Check whether the diagnosis code is set again.


Check again if the diagnosis code is set in the ACC/FCM-ECU.
(1)Erase the diagnosis code.
(2)Turn the ignition switch from "LOCK" (OFF) position to "ON" position.
(3)Start the engine.
(4)Press the ACC ON/OFF switch to turn the ACC system to ON.
(5)On completion, check that the diagnosis code is set again.

Q. Is diagnosis code No. U0101 set?

Replace the ACC/FCM-ECU (Refer to ).
Intermittent malfunction (Refer to GROUP 00 - How to Cope with Intermittent Malfunction).