Inspection Procedure 2: The interior alarm or exterior alarm does not work normally while the security alarm is triggered.

  • 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 .)


If the interior alarm does not work normally, ETACS-ECU, or combination meter built-in buzzer may have a problem.



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 diagnosis code

Check if diagnosis code is set to the ETACS-ECU.

Q. Is the diagnosis code set?

Troubleshoot the ETACS-ECU. Refer to .
Go to Step 3.

STEP 3. M.U.T.-III other system special function

Using M.U.T.-III, select "Test" from the special function of the combination meter. Execute the following item to check the buzzer. (Refer to Combination Meter )

  • Item 3: Buzzer(AUTO)

Q. Is the check result normal?

Go to Step 4.
Troubleshoot the combination meter. Refer to .

STEP 4. Retest the system

Check that the security alarm works normally.

Q. Is the check result normal?

The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to use Troubleshooting/inspection Service Points - How to Cope with Intermittent Malfunction ).
Replace the ETACS-ECU.