Inspection Procedure 8: The Auto Lamp Function does not Work Normally. <Vehicles without Lighting Control Sensor>



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












OPERATION




COMMENTS ON TROUBLE SYMPTOM




PROBABLE CAUSES



  • Malfunction of the photo sensor
  • Malfunction of the column switch
  • Malfunction of the ETACS-ECU
  • 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. Check that the headlamps operate.



Q. Is the check result normal?





STEP 4. 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 5. Connector check: C-05 photo sensor connector and C-301 ETACS-ECU connector


Q. Is the check result normal?





STEP 6. Wiring harness check between the C-05 photo sensor connector terminal No. 1, 2, 3 and C-301 ETACS-ECU connector terminal No. 3, 18, 20



  • Check the power supply lines, earth lines and communication lines for open circuit.

Q. Is the check result normal?





STEP 7. Retest the system



Q. Is the check result normal?





STEP 8. Replace the photo sensor temporarily and retest the system.



Q. Is the check result normal?