Inspection Procedure 18: The FCM switch 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 FCM switch
  • Malfunction of the ETACS-ECU
  • Damaged harness wires and connectors

DIAGNOSIS PROCEDURE


STEP 1. Check the FCM switch.



Q. Is the check result normal?





STEP 2. Resistance measurement at FCM switch connector (earth terminal)


(1)Disconnect the connector, and measure at the wiring harness side.
(2)Measure the resistance between the FCM switch connector (earth terminal) and body earth.
OK: Continuity exists (2 Ω or less)

Q. Is the check result normal?





STEP 3. Check of open circuit in earth line between FCM switch connector and body earth


Q. Is the check result normal?





STEP 4. Check of short to earth, and open circuit in FCMS line between FCM switch connector and ETACS-ECU connector


Q. Is the check result normal?





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




  • When the FCM switch is pressed.
Item No.
Item name
Normal condition
Item 404
FCM switch
ON

  • When the FCM switch is not pressed.
Item No.
Item name
Normal condition
Item 404
FCM switch
OFF
OK: Normal condition is displayed.

Q. Is the check result normal?