Code No. U111B: MCU CAN time-out


caution If there is any problem in the CAN bus lines, an incorrect diagnosis code may be set. Prior to this diagnosis, always diagnose the CAN bus lines.

OPERATION



  • MCU communicates with EV-ECU via CAN.

DIAGNOSIS CODE SET CONDITIONS



  • When the time-out of the MCU CAN data is determined, the diagnosis code No. U111B will be set.

PROBABLE CAUSES



  • Malfunction of CAN data system in the MCU

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III CAN bus diagnosis
Use the M.U.T.-III to diagnose the CAN bus lines.

Q. Is the check result normal?
Go to Step 3.
Repair the CAN bus line. (Refer to GROUP 54C - Troubleshooting .) Then go to Step 2.

STEP 2. Diagnosis code recheck after resetting CAN bus lines
Check again if the diagnosis code No. U111B is set to the EV-ECU.
(1)Erase the stored diagnosis code.
(2)Set the electric motor switch from the LOCK (OFF) position to the ON position.
(3)Check if the diagnosis code is set.

Q. Is the diagnosis code set?
Go to Step 3.
This diagnosis is complete.

STEP 3. Use M.U.T.-III to confirm a diagnosis code of other systems.
Check if the diagnosis code is set to the MCU.

Q. Is the diagnosis code set?
Carry out troubleshooting for the MCU. (Refer to .)
Go to Step 4.

STEP 4. Use M.U.T.-III to confirm a diagnosis code of other systems.
Check if the diagnosis code No. U111B is set to the BMU.

Q. Is the diagnosis code set?
Go to Step 5.
Go to Step 6.

STEP 5. Diagnosis code recheck
Check again if the diagnosis code is set to the EV-ECU.
(1)Erase the stored diagnosis code.
(2)Set the electric motor switch from the LOCK (OFF) position to the ON position.
(3)Check if the diagnosis code is set.

Q. Is the diagnosis code set?
Replace the MCU. (Refer to .)
A poor connection, open circuit of the wiring harness or other intermittent malfunction is present in the CAN bus line between the MCU and EV-ECU (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points, How to Handle Intermittent Malfunction )

STEP 6. Diagnosis code recheck
Check again if the diagnosis code is set to the EV-ECU.
(1)Erase the stored diagnosis code.
(2)Set the electric motor switch from the LOCK (OFF) position to the ON position.
(3)Check if the diagnosis code is set.

Q. Is the diagnosis code set?
Replace the EV-ECU. (Refer to .)
A poor connection, open circuit of the wiring harness or other intermittent malfunction is present in the CAN bus line between the MCU and EV-ECU (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points, How to Handle Intermittent Malfunction )