If the diagnosis
code No. U0141 is set, be sure to diagnose the CAN bus line.
When replacing the ECU, always check that the communication circuit is normal.
DIAGNOSIS FUNCTION
If no signal from ETACS can be received, KOS-ECU sets the diagnosis code No. U0141.
PROBABLE CAUSES
Malfunction of CAN bus line
Malfunction of KOS-ECU
Malfunction of ETACS-ECU
DIAGNOSIS PROCEDURE
STEP 1. M.U.T.-III CAN bus diagnostics
Use M.U.T.-III to diagnose the CAN bus lines.
Q.
Is the check result normal?
Go to Step 2.
Repair the CAN bus line (Refer to GROUP 54C -
Troubleshooting ).
STEP 2. M.U.T.-III other system diagnosis code
Check if any diagnosis code is set to the ETACS-ECU.
Q.
Is the diagnosis code set?
Perform troubleshooting for ETACS (Refer to GROUP 54A -
ETACS -
Troubleshooting ).
Go to Step 3.
STEP 3. M.U.T.-III other system diagnosis code
Check if diagnosis code No.U0141 is set to the combination meter.
Q.
Is the diagnosis code set?
Go to Step 4.
Go to Step 5.
STEP 4. Check whether the diagnosis code is reset.
Recheck if the diagnosis code is set to the KOS-ECU.
(1)Erase the diagnosis code.
(2)Turn the power supply mode of the engine switch from OFF to ON.
(3)Check if the diagnosis code is set.
Q.
Is the diagnosis code set?
Replace the ETACS-ECU.
Intermittent malfunction is suspected (Refer to GROUP 00 -
How to Use Troubleshooting/Inspection
Service Points -
How to Cope with Intermittent Malfunction ).
STEP 5. Check whether the diagnosis code is reset.
Recheck if the diagnosis code is set.
(1)Erase the diagnosis code.
(2)Turn the power supply mode of the engine switch from OFF to ON.
(3)Check if the diagnosis code is set.
Q.
Is the diagnosis code set?
Replace KOS-ECU and register the ID codes (Refer to ).
Intermittent malfunction is suspected (Refer to GROUP 00 -
How to Use Troubleshooting/Inspection
Service Points -
How to cope with Intermittent Malfunction ).
Repair the CAN bus line (Refer to GROUP 54C -
Troubleshooting 
).