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Home >> Lexus >> 2012 >> IS 250 Base, AWD >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Control System (Diagnostic Codes (P0190-P062F)) >> SFI System >> DTC P0604: Internal Control Module Random Access Memory (RAM) Error >> Procedure
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DTC P0604: Internal Control Module Random Access Memory (RAM) Error: Procedure

  1. READ OUTPUT DTC (DTC P0604) 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Clear the DTCsRefer to DTC CHECK / CLEAR .
    5. Turn the Techstream off.
    6. Turn the engine switch off.
    7. Disconnect the Techstream.
    8. Disconnect the cable from the negative (-) battery terminal and wait for 1 minute.
    9. Connect the cable to the negative (-) battery terminal.
    10. Connect the Techstream to the DLC3.
    11. Turn the engine switch on (IG).
    12. Turn the Techstream on.
    13. Wait for 16 seconds.
    14. Enter the following menus: Powertrain / Engine / Trouble Codes.
    15. Read the DTCs.

      Result

      Result Proceed to
      DTC is not output A
      DTC P0604 is output B

    B → See step   3 

    A → See step   2 

  2. CHECK FOR INTERMITTENT PROBLEMS. Refer to  CHECK FOR INTERMITTENT PROBLEMS 
  3. REPLACE ECM. Refer to  REMOVAL