Inspection Procedure 1: The ignition switch (ACC) signal is not received.


caution
  • 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 .)

COMMENTS ON TROUBLE SYMPTOM



PROBABLE CAUSES



  • Malfunction of the ETACS-ECU
  • Malfunction of the ignition switch <Vehicles without KOS>
  • Malfunction of the OSS-ECU <Vehicles with one touch start system>
  • Damaged harness wires and connectors

DIAGNOSIS PROCEDURE


STEP 1. Voltage measurement at ETACS-ECU connector (ACC terminal).


(1)Disconnect the connector, and measure at the wiring harness side.
(2)Turn the ignition switch to the "ACC" position.
(3)Check the voltage between the ETACS-ECU connector (ACC terminal) and body earth.
OK: System voltage

Q. Is the check result normal?







STEP 2. Check the M.U.T.-III Diagnosis code for other systems



Q. Is the diagnosis code set?





STEP 3. Ignition switch check



Q. Is the check result normal?





STEP 4. Check of short to power supply, short to earth, and open circuit in ACC line between ignition switch (ACC) <Vehicles without KOS> or OSS-ECU (ACC) <Vehicles with one touch start system> and ETACS-ECU connector.


Q. Is the check result normal?





STEP 5. M.U.T.-III data list




  • Turn the ignition switch to the ACC position.
Item No.
 Item name
 Normal condition
Item 288
 ACC switch
 ON
OK: Normal condition is displayed.

Q. Is the check result normal?