INSPECTION PROCEDURE 9: Sometimes the rain sensitive wiper function works even though there is no rainfall. <Vehicles with lighting control sensor>


caution Whenever ECU is replaced, ensure that the input and output signal circuits are normal.

COMMENTS ON TROUBLE SYMPTOM
The lighting control sensor may be defective or a failure in the lighting control sensor (rain sensor) adaptation is suspected.

PROBABLE CAUSES

  • Malfunction of the lighting control sensor

  • Lighting control sensor (rain sensor) adaptation failure

DIAGNOSTIC PROCEDURE

STEP 1. Lighting control sensor installation surface check
Visually check the presence of scratches or air bubbles (diameter of 5 mm or more) on the windshield to which the lighting control sensor is installed.

Q. Is the check result normal?
Go to Step 2.
Replace the windshield (Refer to GROUP 42 - Windshield Removal and Installation ).

STEP 2. Windshield wiper operation check
Check that the windshield wipers work normally.

Q. Is the check result normal?
Go to Step 3.
Refer to Inspection procedure 3 .

STEP 3. M.U.T.-III diagnosis code
Check if CAN converter-ECU-related diagnosis code is set.

Q. Is the diagnosis code set?
Diagnose the CAN converter-ECU. Refer to GROUP 54A - Head lamp Diagnosis Code Chart .
Go to Step 4.

STEP 4. M.U.T.-III diagnosis code
Check if a lighting control sensor diagnosis code is set.

Q. Is the diagnosis code set?
Diagnose the lighting control sensor. (Refer to GROUP 54A - Diagnosis Code Chart ).
Go to Step 5.

STEP 5. M.U.T.-III diagnosis code
Check if an ETACS-related diagnosis code is set.

Q. Is the diagnosis code set?
Diagnose the ETACS-ECU. Refer to GROUP 54A - ETACS .
Go to Step 6.

STEP 6. Lighting control sensor installation condition check
Check if the lighting control sensor is installed into the windshield securely.

Q. Is the check result normal?
Perform the lighting control sensor (rain sensor) adaptation (Refer to Lighting Control Sensor (Rain Sensor) Adaptation ), and then go to Step 7 .
Repair the lighting control sensor installation in the windshield. (Refer to GROUP 54A - Lighting Control Sensor Removal and Installation ).

STEP 7. Check of the troubles
Perform the adaptation, and then check the operation according to the following procedures.
(1)Check that the surface of windshield is dry.
(2) Apply water to the surface of windshield glass (the lighting control sensor receiver).

Q. Does the wiper work?
Works once or more. : Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction ).
Not work : Perform troubleshooting for the raindrops responding wiper function (Refer to Inspection Procedure 7: the raindrops responding wiper function does not work at all ).