Code No. U111B: MCU Time-out

caution

If diagnosis code No. U111B is set from the BMU, diagnose the CAN bus line.

caution

Before replacing the ECU, ensure that the communication circuit is normal.

TROUBLE JUDGMENT

Check Conditions

5 seconds elapse after the electric motor switch is turned ON, or 5 seconds elapse after the main battery starts to be charged.
During the CAN communication.
The following diagnosis code is not set.

U1073: Bus off

Judgement Criterion

For more than 3 seconds, the data cannot be received from the MCU.

COMMENT ON TROUBLE SYMPTOM

Current trouble

The connectors and the harnesses of the CAN bus line may be failed between the BMU and the MCU. The power supply system of the MCU may be failed. The MCU or the BMU may be failed.

Past trouble

Carry out diagnosis with particular emphasis on harnesses or connectors in the CAN bus lines between the BMU and the MCU. Diagnose the power supply system of the MCU. For diagnosis procedures, refer to "How to treat past trouble" (refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Treat Past Trouble

note

In case of the past trouble, you cannot find any malfunctions by the M.U.T.-III CAN bus diagnostics even if there is any failure in the CAN bus lines. Therefore, check the CAN bus lines in the same way as - How to cope with intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points

). You can narrow down the possible cause of the trouble by referring to the diagnosis code which is output to each ECU that has the CAN communication (Refer to GROUP 54C - Explanation about the M.U.T.-III CAN Bus Diagnostics

FAIL-SAFE AND BACKUP FUNCTION

Not available

PROBABLE CAUSES

The harnesses and connectors are failed.
The MCU is failed.
The BMU is failed.

DIAGNOSIS PROCEDURE

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

Using M.U.T.-III, perform CAN bus line diagnosis.

Q. Is the check result normal?

	Go to Step 2 .

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

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

Confirm whether the diagnosis codes are set from MCU.

Q. Is the diagnosis code set?

	Perform the troubleshooting of the MCU (Refer to ).

	Go to Step 3 .

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

Check that the other ECU performing CAN communication with MCU sets diagnosis code No. U111B (Refer to GROUP 54C - CAN Communication-related Diagnosis Code (U Code) Table

Q. Is the diagnosis code set?

	Go to Step 4 .

	Go to Step 5 .

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

Reconfirm whether the diagnosis codes are set from BMU.

Erase the diagnosis codes being set.
Electric motor switch: "LOCK" (OFF) → ON
Confirm whether the diagnosis codes are set.

Q. Is the diagnosis code set?

	Replace the MCU. Then go to Step 6 .

	Intermittent malfunction in CAN bus line between BMU and MCU (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

Reconfirm whether the diagnosis codes are set from BMU.

Erase the diagnosis codes being set.
Electric motor switch: "LOCK" (OFF) → ON
Confirm whether the diagnosis codes are set.

Q. Is the diagnosis code set?

	Replace the BMU. Then go to Step 6 .

	Intermittent malfunction in CAN bus line between BMU and MCU (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

Reconfirm whether the diagnosis codes are set from BMU.

Erase the diagnosis codes being set.
Electric motor switch: "LOCK" (OFF) → ON
Confirm whether the diagnosis codes are set.

Q. Is the diagnosis code set?

	Go to Step 1 .

	Check end.

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