Code No.U0168 KOS/WCM CAN timeout



caution
  • If diagnosis code No. U0168 is stored in the ETACS-ECU, always diagnose the CAN bus line.
  • Before replacing the ECU, ensure that the power supply circuit, the earth circuit and the communication circuit are normal.

DIAGNOSTIC FUNCTION


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

JUDGEMENT CRITERIA


After the following statuses continue to be true for 5 seconds, if the communication with the KOS-ECU 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 stored in the KOS-ECU.

Q. Is the diagnosis code stored?

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

Go to Step 3.

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


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

Q. Is the diagnosis code stored?

Go to Step 4.

Go to Step 5.

STEP 4. Check whether the diagnosis code is stored again.


Check again if the diagnosis code is stored in 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 stored.

Q. Is the diagnosis code stored?

Replace the KOS-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 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 stored again.


Check again if the diagnosis code is stored in 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 stored.

Q. Is the diagnosis code stored?

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 and the ETACS-ECU (Refer to GROUP 00 - How to use Troubleshooting/inspection Service Points - How to Cope with Intermittent Malfunction ).