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Home >> Lexus >> 2020 >> LS 500 Base, RWD >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - Diagnostic Codes (09 Of 14) >> SFI System >> DTC P0604-44: Internal Control Module Random Access Memory (RAM) Error Data Memory Failure [12/2017 - 10/2020] >> Procedure
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DTC P0604-44: Internal Control Module Random Access Memory (RAM) Error Data Memory Failure [12/2017 - 10/2020]: Procedure

  1. CLEAR DTC 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Clear the DTCs.

      Powertrain > Engine > Clear DTCs 

    5. Turn the engine switch off.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  2

  2. READ OUTPUT DTC (DTC P0604-44) 
    1. Disconnect the cable from the negative (-) battery terminal and wait for 1 minute.
    2. Connect the cable to the negative (-) battery terminal.
    3. Connect the Techstream to the DLC3.
    4. Turn the engine switch on (IG).
    5. Turn the Techstream on.
    6. Wait 16 seconds or more.
    7. Enter the following menus: Powertrain / Engine / Trouble Codes.
    8. Read the DTCs.

      Powertrain > Engine > Trouble Codes 

      Result

      Result Proceed to
      DTCs are not output A
      DTC P0604-44 is output B

    Result: 

    CHECK FOR INTERMITTENT PROBLEMS. Refer to  CHECK FOR INTERMITTENT PROBLEMS [12/2017 - ] 

    Result: 

    REPLACE ECM. Refer to  REMOVAL [12/2017 - 09/2018]  , or refer to  REMOVAL [09/2018 - 10/2020]