Inspection Procedure 3: The Headlamps Illuminate at Low-beam (High-beam does not Illuminate) Regardless of the Lighting Switch Positions.


caution Whenever the ECU is replaced, ensure that the power supply circuit, the earth circuit and the communication circuit are normal.

COMMENTS ON TROUBLE SYMPTOM



PROBABLE CAUSES



  • Malfunction of column switch
  • Malfunction of the ETACS-ECU
  • Malfunction of the photo sensor <Vehicles without lighting control sensor>
  • Malfunction of the lighting control sensor <Vehicles with lighting control sensor>
  • Damaged harness wires and connectors

DIAGNOSIS PROCEDURE


STEP 1. M.U.T.-III CAN bus diagnostics



Q. Is the check result normal?





STEP 2. M.U.T.-III diagnosis code



Q. Is the diagnosis code set?





STEP 3. M.U.T.-III other system diagnosis code



Q. Is the diagnosis code set?







STEP 4. M.U.T.-III other system diagnosis code



Q. Is the diagnosis code set?





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




  • Turn the lighting switch to the "AUTO" position.
Item No.
 Item name
 Normal condition
Item 348
 Headlamp switch (auto)
 ON
OK: Normal condition is displayed.

Q. Is the check result normal?





STEP 6. Photo sensor <Vehicles without lighting control sensor> or lighting control sensor <Vehicles with lighting control sensor> check



Q. Is the check result normal?





STEP 7. Retest the system



Q. Is the check result normal?