Inspection Procedure

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

      MAIN BODY 

      INTELLIGENT TESTER MAIN BODY REFERENCE CHART
      
      

      Tester Display	Measurement Item / Range	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 REFERENCE CHART
      
      

      Tester Display	Measurement Item / Range	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. 

NG:  Go to step  4

OK: Go to next step 

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

      COMBI SW 

      INTELLIGENT TESTER COMBI SW REFERENCE CHART
      
      

      Tester Display	Measurement Item / Range	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 REFERENCE CHART
      
      

      Tester Display	Measurement Item / Range	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: END (REPLACE WINDSHIELD WIPER SWITCH)  (See REMOVAL )

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

   Standard resistance 

   TESTER CONNECTION SPECIFIED CONDITION REFERENCE CHART
   
   

   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

   Fig 1: Identifying L12 ECU And M2 Sensor Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

   Standard voltage 

   TESTER CONNECTION SPECIFIED CONDITION REFERENCE CHART
   
   

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

   Fig 2: Identifying L12 Main Body ECU Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

NG: REPLACE MAIN BODY ECU 

OK: REPLACE AUTOMATIC LIGHT CONTROL SENSOR  (See REMOVAL  )