Inspection Procedure 2: The ignition switch (IG1) signal is not received.


caution Before replacing the ECU, ensure that the power supply circuit, the earth circuit and the communication circuit are normal.

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 KOS>
  • Damaged harness wires and connectors

DIAGNOSIS PROCEDURE


STEP 1. Connector check: C-417 ETACS-ECU connector, C-14 OSS-ECU connector <Vehicles with KOS>


Q. Is the check result normal?







STEP 2. Ignition switch check



Q. Is the check result normal?





STEP 3. Voltage measurement at the C-417 ETACS-ECU connector.


(1)Measure by backprobing without disconnecting the connector.
(2)Turn the ignition switch to the "ON" position.
(3)Measure the voltage between the C-417 ETACS-ECU connector terminal No. 6 and the body earth.
OK: System voltage

Q. Is the check result normal?





STEP 4. Wiring harness check between the C-417 ETACS-ECU connector terminal No. 6 and the ignition switch (IG1) <Vehicles without KOS> or C-14 OSS-ECU connector terminal No. 7 <Vehicles with KOS>



Q. Is the check result normal?







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



    Turn the ignition switch to the ON position.
Item No.
 Item name
 Normal condition
Item 254
 IG voltage
 System voltage
OK: Normal condition is displayed.

Q. Is the check result normal?