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HOMESERVICE MANUALSSUBARU2004BAJA BASE, STANDARDREPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT CARSECTION 161 (DIAGNOSTIC TROUBLE CODE (DTC) DETECTING CRITERIA (STI))DIAGNOSTIC TROUBLE CODE (DTC) DETECTING CRITERIADTC P0604: INTERNAL CONTROL MODULE RANDOM ACCESS MEMORY (RAM) ERROR
2004 Subaru Baja Base, Standard

DTC P0604: Internal Control Module Random Access Memory (Ram) Error

2004 Subaru Baja Base, StandardSECTION DTC P0604: Internal Control Module Random Access Memory (Ram) Error
WARNING: This page is about a different car, the 2004 Subaru Impreza. However, it is still accessible from the selected car via links, so may be relevant.
  1. OUTLINE OF DIAGNOSIS 

    Detect the function abnormality of the micro-computer (RAM).

    Judge NG when either the main CPU normal RAM or sub CPU normal RAM is abnormal. Judge OK when both of them are normal.

    At initial routine, write the data to all area of RAM. Judge OK when same data can be read out, and judge NG when same data cannot be read out.

  2. ENABLE CONDITION 
    SECONDARY PARAMETERS AND ENABLE CONDITION CHART

    Secondary Parameters Enable Conditions
    None  

    Perform the diagnosis in the initial routine.

  3. GENERAL DRIVING CYCLE 

    Perform the diagnosis immediately after IG key SW is turned ON.

  4. DIAGNOSTIC METHOD 
    • Abnormality Judgment 

      Judge NG when the malfunction criteria below are completed.

      Judgment Value 

      MALFUNCTION CRITERIA AND THRESHOLD VALUE CHART

      Malfunction Criteria Threshold Value
      Main CPU normal RAM abnormality  
      Write 5AA5A55A, and read out. (All area of RAM) Cannot be read out 5AA5A55A.
      Or write A55A5AA5, and read out. (All area of RAM) Cannot be read out A55A5AA5.
      Sub CPU normal RAM abnormality.  
      Write 5AA5, and read out. (All area of RAM) Cannot be read out 5AA5.
      Or write A55A, and read out. (All area of RAM) Cannot be read out A55A.

      Time Needed for Diagnosis:  100 milliseconds

      Malfunction Indicator Light Illumination:  Illuminates as soon as malfunction occurs.

    • Normality Judgment 

      Judge NG when the malfunction criteria below are completed.

      Judgment Value 

      MALFUNCTION CRITERIA AND THRESHOLD VALUE CHART

      Malfunction Criteria Threshold Value
      Main CPU normal RAM abnormality  
      Write 5AA5A55A, and read out. (All area of RAM) Cannot be read out 5AA5A55A.
      Or write A55A5AA5, and read out. (All area of RAM) Cannot be read out A55A5AA5.
      Sub CPU normal RAM abnormality.  
      Write 5AA5, and read out. (All area of RAM) Cannot be read out 5AA5.
      Or write A55A, and read out. (All area of RAM) Cannot be read out A55A.
  5. DTC CLEAR CONDITION 
    • When the OK idling cycle was completed 40 times in a row
    • When "Clear Memory" was performed
  6. MALFUNCTION INDICATOR LIGHT CLEAR CONDITION 
    • When the OK driving cycle was completed 3 times in a row
    • When "Clear Memory" was performed
  7. FAIL SAFE 

    None

  8. ECM OPERATION AT DTC SETTING 

    Memorize the freeze frame data. (For test mode $02)

RENDER: 1.0x

NO RELATED

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