Code No.U0168 KOS/WCM CAN timeout



caution
  • If the diagnosis code No. U0168 is set to the ETACS-ECU, always diagnose the CAN bus line.
  • Before replacing the ECU, ensure that the communication circuit is normal.

DIAGNOSTIC FUNCTION


If the signal from KOS-ECU or WCM cannot be received, the ETACS-ECU sets the diagnosis code No. U0168.

JUDGMENT CRITERIA


After the following statuses continue to be true for 5 seconds, if the communication with the KOS-ECU or WCM cannot be established for 2,500 ms or more, the ETACS-ECU determines that a problem has occurred.


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 line (Refer to GROUP 54C - Troubleshooting ).

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


Check if diagnosis code is set to the KOS-ECU or WCM.

Q. Is the diagnosis code set to the any of the above?

Set to the KOS-ECU. : Troubleshoot the KOS. Refer to GROUP 42B - Diagnosis Code Chart .

Set to the WCM. : Troubleshoot the WCM. Refer to GROUP 42C - Diagnosis Code Chart .

The diagnosis code is not set. : Go to Step 3.

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


Check if the diagnosis code No. U0168 is set to the SRS-ECU, radio and CD player, combination meter, or A/C-ECU.

Q. Is the diagnosis code set?

Go to Step 4.

Go to Step 5.

STEP 4. Check whether the diagnosis code is reset.


Check again if the diagnosis code is set to the ETACS-ECU.
(1)Erase the diagnosis code.
(2)Turn the ignition switch from "LOCK" (OFF) position to "ON" position.
(3)Check if diagnosis code is set.

Q. Is the diagnosis code set?

Replace the KOS-ECU or WCM.

The trouble can be an intermittent malfunction such as a poor connection or open circuit in the CAN bus lines between the KOS-ECU or WCM and the ETACS-ECU (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.


Check again if the diagnosis code is set to the ETACS-ECU.
(1)Erase the diagnosis code.
(2)Turn the ignition switch from "LOCK" (OFF) position to "ON" position.
(3)Check if diagnosis code is set.

Q. Is the diagnosis code set?

Replace the ETACS-ECU.

The trouble can be an intermittent malfunction such as a poor connection or open circuit in the CAN bus lines between the KOS-ECU or WCM and the ETACS-ECU (Refer to GROUP 00 - How to use Troubleshooting/inspection Service Points - How to Cope with Intermittent Malfunction ).