P0181

DTC P0181 - FUEL TEMPERATURE SENSOR "A" CIRCUIT RANGE/PERFORMANCE

OUTLINE OF DIAGNOSIS
Detect the malfunction of fuel temperature sensor output property. Perform the diagnosis in two methods; namely, drift diagnosis and stuck diagnosis. Judge NG when either of them results in NG, and judge OK when both of them result in OK.

Drift Diagnosis
Normally fuel temperature is lower than engine coolant temperature. When the fuel temperature becomes higher than the engine coolant temperature, the range is considered to be shifted, and make an NG judgment.




COMPONENT DESCRIPTION




ENABLE CONDITION

GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.

DIAGNOSTIC METHOD




- Abnormality Judgment
Judge NG when the continuous time of completing the malfunction criteria becomes more than 120 seconds.




- Normality Judgment
Judge OK when the malfunction criteria are completed.

- Stuck Diagnosis
If the fuel temperature which might rise along with the engine idling (the cumulative amount of intake air after engine starting is large) does not increase, the engine is considered to be stuck and make an NG judgment.




ENABLE CONDITION

GENERAL DRIVING CYCLE
Always perform diagnosis continuously.

DIAGNOSTIC METHOD




- Abnormality Judgment
Judge NG when the malfunction criteria are completed.




- Normality Judgment
Judge OK when the malfunction criteria are 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 completed 3 times in a row
- When "Clear Memory" was performed

FAIL SAFE
None

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