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Home >> Toyota >> 2012 >> Prius Plug-in >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 137 (Solar Ventilation System (Except Plug-In) (Diagnostics & Circuit Tests)) >> Solar Ventilation System >> Circuit Tests >> IG Signal Circuit >> Procedure
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IG Signal Circuit: Procedure

WARNING: This page is about a different variant/trim than selected.
  1. READ VALUE USING TECHSTREAM 
    1. Connect the Techstream to the DLC3.
    2. Turn the power switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Body Electrical / Air Conditioner / Data List.
    5. Check the value(s) by referring to the table below.
      AIR CONDITIONER

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Solar IG Status Solar ventilation ECU IG status / OFF or ON OFF: Power switch off
      ON: Power switch on (IG)
      When OFF is displayed, a malfunction in the solar ventilation ECU is suspected.

      OK

      The display is as specified in the Normal Condition column.

      Result

      Result Proceed to
      NG A
      OK
      (When troubleshooting according to Problem Symptoms Table (for Solar Ventilation System))
      B
      OK
      (When troubleshooting according to Problem Symptoms Table (for Air Conditioning System))
      C

    B → See step   3 

    C → See step   5 

    A: Go to next step 

  2. CHECK HARNESS AND CONNECTOR (SOLAR VENTILATION ECU - BATTERY) 
    1. Disconnect the solar ventilation ECU connector.
      Fig 1: Identifying Harness And Connector (Solar Ventilation ECU - Battery)
      GTY220247Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      L22-25 (IG) - Body ground Power switch off Below 1 V
      L22-25 (IG) - Body ground Power switch on (IG) 11 to 14 V
      TEXT IN ILLUSTRATION

      *1 Front view of wire harness connector
      (to Solar Ventilation ECU)

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → See step   4 

  3. PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE  
  4. REPLACE SOLAR VENTILATION ECU. Refer to  REMOVAL 
  5. PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE