Code No. U0101: T/M CAN timeout



caution
  • If diagnosis code No. U0101 is set in the multivision display, always diagnose the CAN bus lines.
  • Whenever the ECU is replaced, ensure that the communication circuit is normal.
note When the diagnosis codes relating to the CAN communication error are set, make sure of the vehicle equipment. When the vehicle is not equipped with the system the multivision display communicates to, the diagnosis code is always set. This is not abnormal.


TROUBLE JUDGEMENT


The multivision display receives transmission control system-related signal from the A/T-ECU through the gateway-ECU (for smartphone link display audio) via CAN bus lines. If the display unit cannot receive the necessary signals, diagnosis code No. U0101 will be set.

COMMENTS ON TROUBLE SYMPTOM


Current trouble
Past trouble

PROBABLE CAUSES




DIAGNOSIS PROCEDURE


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


Use the M.U.T.-III to diagnose the CAN bus lines.

Q. Is the check result normal?

Go to Step 2.

Repair the CAN bus lines. (Refer to GROUP 54C - Troubleshooting ). Repair the CAN bus line and go to Step 7.

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


Check whether the A/T system diagnosis codes are set or not.

Q. Is the diagnosis code set?

Diagnose the A/T-ECU troubleshooting (GROUP 23A - Troubleshooting).

Go to Step 3.

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


Check if a diagnosis code, which relates to CAN communication-linked systems below, is set.

Q. Is the diagnosis code set?

Go to Step 4.

Go to Step 5.

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


Recheck if the diagnosis code is set.
(1)Erase the diagnosis code.
(2)Turn the ignition switch to "ON" position.
(3)On completion, check that the diagnosis code is not set again.

Q. Is the diagnosis code set?

Replace A/T-ECU and then go to Step 6.

A poor connection, open circuit or other intermittent malfunction is present in the CAN bus lines between the A/T-ECU and the multivision display (Refer to GROUP 00 - How to use troubleshooting/Inspection Service Points).

STEP 5. Check whether the diagnosis code is set again.


Recheck if the diagnosis code is set.
(1)Erase the diagnosis code.
(2)Turn the ignition switch to "ON" position.
(3)On completion, check that the diagnosis code is not set again.

Q. Is the diagnosis code set?

Replace gateway-ECU (for smartphone link display audio) (Refer to ) and then go to Step 6.

A poor connection, open circuit or other intermittent malfunction is present in the CAN bus lines between the A/T-ECU and the multivision display (Refer to GROUP 00 - How to use troubleshooting/Inspection Service Points).

STEP 6. Check whether the diagnosis code is set again.


Recheck if the diagnosis code is set.
(1)Erase the diagnosis code.
(2)Turn the ignition switch to "ON" position.
(3)On completion, check that the diagnosis code is not set again.

Q. Is the diagnosis code set?

Replace multivision display (Refer to ) and then go to Step 7.

The procedure is complete.

STEP 7. Check whether the diagnosis code is set again.


Recheck if the diagnosis code is set.
(1)Erase the diagnosis code.
(2)Turn the ignition switch to "ON" position.
(3)On completion, check that the diagnosis code is not set again.

Q. Is the diagnosis code set?

Go to Step 1.

The procedure is complete.