The ECM sets DTC P0071 when the ambient air temperature (AAT) sensor reading does not correlate with the other temperature sensor readings at ignition ON.
Item | Detecting Condition | Possible Cause | |
Case1 | DTC Strategy |
•
Rationality check | 1. Poor connection 2. AATS |
Enable Conditions |
•
Vehicle speed > 40km/h
•
40kg/h < Mass air flow < 60~220kg/h
•
ECT > 60 °C(140 °F)
•
Duration of NO fuel cut off > 50 sec. | ||
Threshold Value |
•
l AAT - Modeled AAT l > 20 ℃(68 °F) | ||
Diagnostic Time |
•
5 sec. | ||
Case2 | DTC Strategy |
•
Plausibility check
•
Monitor at cold condition | |
Enable Conditions |
•
Soaking time engine stop ECT 0 ℃(32 °F) > 5hr
•
Soaking time engine stop ECT 90 ℃(194 °F) > 7hr
•
Block heater not detected
•
ECT < 50 ℃(122 °F)
•
ECT - ECT at start < -3 ℃(26.6 °F)
•
Time after engine start < 30 sec. | ||
Threshold Value |
•
I Ref. temp - AAT I at cranking > 20 ℃(68 °F) * Ref. temp : 2 of 3 signals are selected and averaged, and the other signal which has the biggest deviation is excluded | ||
Diagnostic Time |
•
5 sec. | ||
MIL ON Condition |
•
2 driving cycles | ||
