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How To Proceed With Troubleshooting

WARNING: This page is about a different car, the 2011 Toyota Avalon. However, it is still accessible from the selected car via links, so may be relevant.

HINT: 

Use this procedure to troubleshoot the engine immobilizer system.

Techstream should be used in steps 4, 5 and 7.

  1. VEHICLE BROUGHT TO WORKSHOP 

    NEXT: Go to next step 

  2. CUSTOMER PROBLEM ANALYSIS CHECK AND SYMPTOM CHECK 

    NEXT: Go to next step 

  3. CRANK ENGINE FOR MORE THAN 10 SECONDS 

    NEXT: Go to next step 

  4. CHECK FOR DTCS 
    1. Check for DTCs and note any codes that are output.
    2. Delete the DTC.
    3. Recheck for DTCs. Based on the DTC output, try to force output of the same SFI system DTC or engine immobilizer system DTC by simulating the operation indicated by the DTC.
      1. If the DTC does not reoccur, proceed to A.
      2. If the SFI system DTC reoccurs, proceed to B.
      3. If the engine immobilizer system DTC reoccurs, proceed to C.

      B → Go to  SFI SYSTEM  SFI SYSTEM 

      C → Go to   8 step 8 

      A: Go to next step 

  5. READ VALUE OF TECHSTREAM 
    1. Connect Techstream to the DLC3.
    2. Turn the ignition switch ON.
    3. Turn the tester on.
    4. Select the following menu items: Body Electrical / Immobilizer / Data List.
    5. Read the Data List according to the display on the tester.
      IMMOBILIZER:

      Tester Display Measurement Item/Range Normal condition Diagnostic Note
      KEY SW Unlock warning switch signal/ON or OFF ON: Key is in ignition key cylinder
      OFF: No key is in ignition key cylinder      		 -

      OK

      ON (Key is in ignition key cylinder) appears on the screen.

      NG → Go to  DTC B2780: Push Switch / Key Unlock Warning Switch Malfunction  DTC B2780 

      OK: Go to next step 

  6. PROBLEM SYMPTOMS TABLE 
    1. If the fault is not listed on the problem symptoms table, proceed to A.
    2. If the fault is listed on the problem symptoms table, proceed to B.

      B → Go to   8 step 8 

      A: Go to next step 

  7. OVERALL ANALYSIS AND TROUBLESHOOTING 
    1. DATA LIST/ACTIVE TEST. Refer to DATA LIST / ACTIVE TEST 
    2. TERMINALS OF ECU. Refer to TERMINALS OF ECU 

      NEXT: Go to next step 

  8. ADJUST, REPAIR OR REPLACE 

    NEXT: Go to next step 

  9. CONFIRMATION TEST 

    NEXT → END 

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