2009 Toyota Avalon LimitedFACTORY OEM SERVICE PROCEDURE

Inspection Procedure

  1. CHECK OTHER DTC OUTPUT (IN ADDITION TO DTC P0604) 
    1. Connect Techstream to the DLC3.
    2. Turn the ignition switch to ON.
    3. Turn the tester on.
    4. Clear the DTC.
    5. Turn the ignition switch off.
    6. Disconnect the negative battery terminal and wait for 1 minute.
    7. Connect the negative battery terminal.
    8. Turn the ignition switch to ON.
    9. Enter the following menus: Powertrain/Engine/Trouble Codes.
    10. Read the DTCs.

      Result 

      DTC OUTPUT RESULT

      Display (DTC output) Proceed to
      P0604 A
      No output DTC B

      B: CHECK FOR INTERMITTENT PROBLEMS (See  CHECK FOR INTERMITTENT PROBLEMS   ) 

      A :REPLACE ECM (See  REMOVAL   ) 

Chapter Navigation
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Factory Service Tools

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.