P1491

DTC P1491 POSITIVE CRANKCASE VENTILATION (BLOW BY) FUNCTION PROBLEM

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




2. COMPONENT DESCRIPTION




3. ENABLE CONDITION

4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.

5. DIAGNOSIS METHOD




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




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

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

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

8. FAIL SAFE
None

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