Code No.U0131 EPS CAN timeout



caution
  • If diagnosis code No. U0131 is set to 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.
  • When the ETACS-ECU of vehicles without KOS is replaced, the encrypted code of the ignition key needs to be registered to the ETACS-ECU. (If the encrypted code is not registered, the engine cannot be started. Register the encrypted code as described in Immobilizer System - How to Register Key ID .)

DIAGNOSTIC FUNCTION


If the signal from EPS-ECU cannot be received, the ETACS-ECU sets the diagnosis code No. U0131.

JUDGEMENT CRITERIA


After the following statuses continue to be true for 5 seconds, if the communication with the EPS-ECU cannot be established for 600 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 EPS-ECU.

Q. Is the diagnosis code set?

Troubleshoot the EPS. Refer to GROUP 37 - Troubleshooting .

Go to Step 3.

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


Check if the diagnosis code No. U0131 is set to the engine-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 EPS-ECU.

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