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P1491

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

1. OUTLINE OF DIAGNOSIS
Detect the blow-by hose release abnormality.

Judge as NG when the diagnosis terminal voltage is high.

2. COMPONENT DESCRIPTION






3. ENABLE CONDITION

Enable Conditions:






4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.

5. DIAGNOSTIC METHOD

Abnormality Judgment
Judge as NG when the continuous time of meeting the malfunction criteria below becomes more than 2.5 seconds.






Time Needed for Diagnosis: 2.5 seconds

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

Normality Judgment
Judge as OK and clear the NG when the malfunction criteria below are met.






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

7. MALFUNCTION INDICATOR LIGHT CLEAR CONDITIONS
- When the OK driving cycle is completed 3 times in a row
- When "Clear Memory" is performed

8. FAIL SAFE
None

9. ECM OPERATION AT DTC SETTING
Memorize the diagnostic value and trouble standard value. (For test mode $06)