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Home >> Lexus >> 2007 >> ES 350 >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - DTC P0171 - P0604 >> DTC P0604: Internal Control Module Random Access Memory (RAM) Error >> Inspection Procedure
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Inspection Procedure

  1. CHECK OTHER DTC OUTPUT (IN ADDITION TO DTC P0604) 
    1. Connect the intelligent tester to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the tester on.
    4. Clear the DTC.
    5. Turn the engine switch off.
    6. Disconnect the battery negative terminal and wait for 1 minute.
    7. Connect the battery negative terminal.
    8. Turn the engine switch on (IG).
    9. Enter the following menus: DIAGNOSIS / ENHANCED I / DTC INFO / CURRENT CODES.
    10. Read the DTCs.

      Result 

      RESULT REFERENCE

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

    B: CHECK FOR INTERMITTENT PROBLEMS 

    A: REPLACE ECM (See  REMOVAL  ) 

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