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Inspection Procedure: Procedure

WARNING: This page is about a different car, the 2011 Toyota Corolla. However, it is still accessible from the selected car via links, so may be relevant.
  1. READ VALUE USING TECHSTREAM 
    1. Connect the Techstream to the DLC3.
    2. Turn the ignition switch to ON.
    3. Turn the Techstream on.
    4. Enter the following menus: Body Electrical / Main Body / Data List.
    5. Read the display on the Techstream.
      MAIN BODY (MAIN BODY ECU)

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      IG SW Ignition switch IG signal/ON or OFF ON: Ignition switch ON
      OFF: Ignition switch off
      -

      OK

      Normal conditions listed above are displayed.

    NG → See step   2 

    OK → See step   4 

  2. INSPECT FUSE (ECU-IG NO. 1) 
    1. Remove the ECU-IG No. 1 fuse from the instrument panel junction block.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      ECU-IG No. 1 fuse Always Below 1 Ω

    NG → REPLACE FUSE 

    OK: Go to next step 

  3. CHECK HARNESS AND CONNECTOR (IG POWER SOURCE CIRCUIT) 
    1. Measure the voltage between the loading slot of the fuse and body ground.
      Fig 1: Identifying ECU-IG NO. 1 Fuse Terminal
      GTY207264Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      ECU-IG No. 1 fuse terminal - Body ground Ignition switch off Below 1 V
      Ignition switch ON 11 to 14 V

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → REPLACE MAIN BODY ECU (INSTRUMENT PANEL JUNCTION BLOCK) 

  4. PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE