Inspection Procedure 4: Vehicle power does not turn ON. (Not possible with power supply mode ON only)



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 OSS-ECU
  • Malfunction of ETACS-ECU
  • Damaged harness wires and connectors

DIAGNOSIS PROCEDURE


STEP 1. M.U.T.-III diagnosis code



Q. Is the diagnosis code set?





STEP 2. Voltage measurement at ETACS-ECU connector (IG1 terminal)


(1)With the ETACS-ECU connector kept connected, measure by backprobing.
(2)Using the M.U.T.-III, set the forced power supply output to "IG-ON".(Refer to .)
(3)Measure the voltage between the ETACS-ECU connector (IG1 terminal) and body earth.
OK: System voltage

Q. Is the check result normal?





STEP 3. Check of the troubles



Q. Is the check result normal?