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Home >> Subaru >> 2004 >> Forester XT, Standard >> Repair and Diagnosis (Single Page) >> Engine Performance >> Testing & Diagnosis >> Diagnostic Trouble Code (DTC) Detecting Criteria (H4DOTC) >> Diagnostic Trouble Code (DTC) Detecting Criteria >> DTC P0604: Internal Control Module Random Access Memory (Ram) Error
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DTC P0604: Internal Control Module Random Access Memory (Ram) Error

  1. OUTLINE OF DIAGNOSIS 

    Zero clear all the normal RAM area on initial routine, and judge NG when the sum of all cleared RAMs is any value except zero.

  2. ENABLE CONDITION 
    ENABLE CONDITION CHART

    Secondary Parameters Enable Conditions
    Ignition switch OFF --> ON

    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 

    Judge NG when the malfunction criteria below are completed.Judge OK and clear NG when the malfunction criteria below are not completed.

    Judgment Value 

    JUDGMENT VALUE CHART

    Malfunction Criteria Threshold Value
    Sum of RAM data after data clear Not = 0

    Time Needed for Diagnosis:  100 milliseconds

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

  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)