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How To Proceed With Troubleshooting

WARNING: This page is about a different car, the 2003 Toyota 4Runner. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: Troubleshoot in accordance with the procedures on the following pages.
  1. Vehicle Brought To Workshop 
  2. Customer Problem Analysis Check And Problem Symptom Confirmation 
  3. Crank Engine For More Than 10 Seconds 
  4. Check Diagnostic Trouble Code 
    1. Check for a DTC.
      1. When any of code B2780, B2784, B2794, B2795, B2796, B2797, B2798 or B2799 is output, proceed to A.
      2. When a code except B2780, B2784, B2794, B2795, B2796, B2797, B2798 or B2799 is output, proceed to B.
    1. A : Go To Next Step 
    2. B : Go To SFI System (See  SFI SYSTEM  ) 
  5. Read Value Of Hand-Held Tester (Immobilizer ECU (Transponder Key ECU Assy) (Switch Condition) 
    1. Connect the hand-held tester to the DLC3.
    2. Turn the ignition switch ON and push the hand-held tester main SW ON.
    3. Select the item "KEY SW" in the "DATA LIST" and read its value displayed on the hand-held tester.

    Transponder Key ECU: 

    ECU TRANSPONDER KEY DATA LIST

    Item Measurement Item/Display (Range) Normal Condition
    KEY SW Unlock warning SW signal/ON or OFF ON: Key is in the IG key cylinder OFF: Key is not in IG key cylinder
    1. NG : Go To DTC B2780 (See  DTC B2780 PUSH SWITCH/KEY UNLOCK WARNING SWITCH MALFUNCTION  ) 
    2. OK : Go to Next Step 
  6. Check Diagnostic Trouble Code Of Transponder Key ECU Assy 
    1. Check for a DTC and make a note of the code that is output.
    2. Delete the DTC.
    3. Check if the DTC will be output once again, when the problem symptom is simulated based on the noted code.
      1. Without an output of the code, proceed to A.
      2. With an output of the code, proceed to B.
    1. A : Go to Next Step 
    2. B : Go to step   8 
  7. (See PROBLEM SYMPTOMS TABLE  ) 
    1. Without an applicable problem symptoms table, proceed to A.
    2. With an applicable problem symptoms table, proceed to B.
    1. A : Go to Next Step 
    2. B : Go to step   9 
  8. According To Problem Symptom, Perform Troubleshooting 
    1. (SeePRE-CHECK )
      1. Inspect with the hand-held tester (ECU data monitor).
      2. Inspect with the hand-held tester (Active test).
    2. (SeeTERMINALS OF ECU )
  9. Adjust, Repair Or Replace 
    1. END 
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