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Home >> Lexus >> 2024 >> RX 500h >> Repair and Diagnosis >> External Pages >> Different car >> Section 110 (Stop And Start System - Diagnostic Codes) >> Stop And Start System >> DTC P0604-44: Internal Control Module Random Access Memory (RAM) Error Data Memory Failure [10/2022 - ] >> Procedure

DTC P0604-44: Internal Control Module Random Access Memory (RAM) Error Data Memory Failure [10/2022 - ]: Procedure

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  1. CLEAR DTC 
    1. Clear the DTCs.

      Powertrain > Stop and Start > Clear DTCs 

    2. Turn the ignition switch off.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  2

  2. READ OUTPUT DTC (DTC P0604-44) 

    Pre-procedure1

    • Disconnect the cable from the negative (-) battery terminal and wait for 1 minute.
    • Connect the cable to the negative (-) battery terminal.
    • Turn the ignition switch to ON.
    • Wait 16 seconds or more.
    • Read the DTCs.

      Powertrain > Stop and Start > Trouble Codes 

      Result

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

    Post-procedure1

    • None.

    Result: 

    USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [10/2022 - ] 

    Result: 

    REPLACE ENGINE STOP AND START ECU. Refer to  REMOVAL [10/2022 - ]