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How To Proceed With Troubleshooting

WARNING: This page is about a different car, the 2008 Lexus RX 350. However, it is still accessible from the selected car via links, so may be relevant.

HINT:

  1. VEHICLE BROUGHT TO WORKSHOP 
  2. CUSTOMER PROBLEM ANALYSIS CHECK AND SYMPTOM CHECK 
  3. CRANK ENGINE FOR MORE THAN 10 SECONDS 
  4. CHECK FOR DTCS 
    1. Check for DTCs and note any codes that are output.
    2. Delete the DTCs.
    3. Recheck for DTCs. Try to prompt the DTC (SFI system and engine immobilizer system) by simulating the original activity that the DTC suggested.
      1. If the DTC does not reoccur, proceed to A.
      2. If the DTC (SFI system) reoccurs, proceed to B.
      3. If the DTC (engine immobilizer system) reoccurs, proceed to C.

    B: Go to  SFI SYSTEM 

    C: Go to step   8 

    A: Go to next step. 

  5. READ VALUE OF INTELLIGENT TESTER ((IMMOBILIZER ECU (TRANSPONDER KEY ECU ASSEMBLY) (SWITCH CONDITION)) 
    1. Connect the intelligent tester to the DLC3.
    2. Turn the ignition switch to the ON position and turn the intelligent tester main switch on.
    3. Select the item KEY SW in the DATA LIST and read its value displayed on the intelligent tester.
      ITEM TABLE

      Item Measurement Item/Display (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
      -

    NG: Go to  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 step   8 

    A: Go to next step. 

  7. OVERALL ANALYSIS AND TROUBLESHOOTING 
    1. Inspection with the intelligent tester (DATA LIST).
    2. Inspection with the intelligent tester (ACTIVE TEST).
    3. See TERMINALS OF ECU  .
  8. ADJUST, REPAIR OR REPLACE 
  9. CONFIRMATION TEST 

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