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P1491

DTC P1491 - POSITIVE CRANKCASE VENTILATION (BLOW-BY) FUNCTION PROBLEM

OUTLINE OF DIAGNOSIS
Detect the blow-by hose release abnormality.
Judge NG when the diagnosis terminal voltage is high.




COMPONENT DESCRIPTION




ENABLE CONDITION

GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.

DIAGNOSIS METHOD




- Abnormality Judgment
Judge NG when the continuous time until completing the malfunction criteria becomes more than 2.5 second.




- Normality Judgment
Judge OK and clear NG when the malfunction criteria is completed.

DTC CLEAR CONDITION
- When the OK idling cycle was completed 40 times in a row
- When "Clear Memory" was performed

MALFUNCTION INDICATOR LIGHT CLEAR CONDITION
- When the OK driving cycle was performed 3 times in a row
- When "Clear Memory" was performed

FAIL SAFE
None

ECM OPERATION AT DTC SETTING
Memorize the freeze frame data. (For test mode $02)