Inspection Procedure

1. Using the intelligent tester or Techstream, read the Data List.
   1. Intelligent tester

      MAIN BODY 

      INTELLIGENT TESTER - MAIN BODY
      
      

      Tester Display	Measurement Item/Display	Normal Condition	Diagnostic Note
      ILLUMINATE RAT	Condition of automatic light control sensor/0 to 235600 Ix	Condition value will be displayed	-

   2. Techstream

      Main Body 

      TECHSTREAM - MAIN BODY
      
      

      Tester Display	Measurement Item/Display	Normal Condition	Diagnostic Note
      Illumination Rate Info	Condition of automatic light control sensor/0 to 235600 Ix	Condition value will be displayed	-

      OK : 

      Condition sign can be displayed. 

OK: Go to step   4 

NG: GO TO NEXT STEP 

1. Disconnect the L12 ECU connector.
2. Disconnect the M2 sensor connector.
3. Measure the resistance according to the value(s) in the table below.
   Fig 1: Checking Harness And Connector (Main Body ECU - Automatic Light Control Sensor And Body Ground)

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Standard resistance 

   MAIN BODY ECU - AUTOMATIC LIGHT CONTROL SENSOR AND BODY GROUND
   
   

   Tester Connection	Condition	Specified Condition
   L12-20 (CLTB) - M2-6 (CLTB)	Always	Below 1 Ω
   L12-19 (CLTS) - M2-5 (CLTS)	Always	Below 1 Ω
   L12-18 (CLTE) - M2-3 (CLTE)	Always	Below 1 Ω
   L12-20 (CLTB) - Body ground	Always	10 kΩ or higher
   L12-19 (CLTS) -Body ground	Always	10 kΩ or higher
   L12-18 (CLTE) - Body ground	Always	10 kΩ or higher

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: GO TO NEXT STEP 

1. Disconnect the L12 ECU connector.
2. Measure the voltage according to the value(s) in the table below.
   Fig 2: Checking Main Body ECU (CLTB Voltage)

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Standard voltage 

   MAIN BODY ECU (CLTB VOLTAGE)
   
   

   Tester Connection	Switch Condition	Specified Condition
   20 (CLTB) - Body ground	Engine switch on (IG)	11 to 14 V

NG: REPLACE MAIN BODY ECU 

OK: REPLACE AUTOMATIC LIGHT CONTROL SENSOR (See  ON-VEHICLE INSPECTION   ) 

1. Using the intelligent tester or Techstream, read the Data List.
   1. Intelligent tester

      COMBI SW 

      INTELLIGENT TESTER - COMBI SW
      
      

      Tester Display	Measurement Item/Display	Normal Condition	Diagnostic Note
      LIGHT AUTO SW	Headlight dimmer switch signal (AUTO position)/ON or OFF	ON: Headlight dimmer switch AUTO position OFF: Headlight dimmer switch OFF	-

   2. Techstream

      Combination Switch 

      TECHSTREAM - COMBINATION SWITCH
      
      

      Tester Display	Measurement Item/Display	Normal Condition	Diagnostic Note
      Light Auto Switch	Headlight dimmer switch signal (AUTO position)/ON or OFF	ON: Headlight dimmer switch AUTO position OFF: Headlight dimmer switch OFF	-

      OK : 

      Condition sign can be displayed. 

NG: REPLACE MAIN BODY ECU 

OK: GO TO NEXT STEP 

1. Temporarily replace the windshield wiper switch with a new or normally functioning one (see REMOVAL ).
2. Check the windshield wiper switch operation.

   OK : 

   Windshield wiper switch operation is normal. 

NG: REPLACE MAIN BODY ECU 

OK: REPLACE WINDSHIELD WIPER SWITCH  (See REMOVAL )