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 requests the EV-ECU to suppress the torque as necessary in the driving mode.
DIAGNOSIS CODE SET CONDITIONS
If the torque command value from the EV-ECU is a value other than 0 Nm when the diagnosis code No. P1A27 EV-ECU torque command error (MCU) occurs in the driving mode, the MCU will set the diagnosis code No. P1B16.
PROBABLE CAUSES
Malfunction of the MCU
Malfunction of the EV-ECU
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
Check again if the diagnosis code No. P1B16 is set to the MCU.
(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.
The diagnosis is complete.
STEP 3. M.U.T.-III Diagnosis code of other systems
Check if the diagnosis code is set to the EV-ECU.
Q.
Is the diagnosis code set?
Carry out troubleshooting for the EV-ECU. (Refer to .) Then go to Step 4.
Go to Step 4.
STEP 4. Diagnosis code recheck
Check again if the diagnosis code is set to the MCU.
(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 .) Then go to Step 5.
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction .)
STEP 5. Diagnosis code recheck
Check again if the diagnosis code is set to the MCU.
(1)Erase the stored diagnosis code.
(2)Set the electric motor switch from the LOCK (OFF) position to the ON position.
Go to Step 3.
Repair the CAN bus line. (Refer to GROUP 54C - Troubleshooting 
.) Then go to Step 2.