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Home >> Subaru >> 2004 >> Forester X, Automatic >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Diagnostic Trouble Code (DTC) Detecting Criteria (H4SO) >> Diagnostic Trouble Code (DTC) Detecting Criteria >> DTC P0864: TCM Communication Circuit Range/Performance
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DTC P0864: TCM Communication Circuit Range/Performance

  1. OUTLINE OF DIAGNOSIS 
    • Detect the communication malfunction of AT diagnosis.
    • Judge NG when the communication format does not correspond.
  2. ENABLE CONDITION 
    ENABLE CONDITION

    Secondary Parameters Enable Conditions
    Battery voltage "GREATER THAN EQUAL TO" .0V
    Engine speed "GREATER THAN EQUAL TO" 500 rpm
    Ignition switch ON
  3. GENERAL DRIVING CYCLE 

    Perform the diagnosis continuously after starting the engine.

  4. DIAGNOSTIC METHOD 

    Judge NG when the continuous time communication format does not correspond continued for time needed for diagnosis. Judge OK and clear the NG when the communication format corresponds.

    Judgment Value 

    JUDGMENT VALUE

    Malfunction Criteria Threshold Value
    Incorrect pattern in wiring harness for communication "GREATER THAN EQUAL TO" 60 seconds

    Time Needed for Diagnosis:  60 seconds

    Malfunction Indicator Light Illumination:  Illuminates when malfunction occurs in 2 continuous driving cycles.

  5. DTC CLEAR CONDITION 
    • When the OK idling cycle is 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 

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