Component Location
General Description
A value from modeling that have been retrieved from an intake air temperature sensor has been currently been in use for outside temperature detection. However, it is difficult to use this value due to the properties of the turbo charger, because the temperature shows a great increase during the charging. Therefore, the outside temperature sensor is installed in front of the radiator to directly measure the outside temperature.
DTC Description
ECM sets DTC P0071 when the variation of measured ambient air temperature from cold(or warm) engine start is out of range in threshold value(refer to Detecting condition).
DTC Detecting Condition
Item | Detecting Condition | Possible Cause |
DTC Strategy | Plausibility check
| Faulty AAT |
Enable Conditions | Case1 | modeled Temp. AAT < 190.5 °C
change of IAT(between two measurements) <1.5 °C
change of AAT(between two measurements)<1.5 °C
79.5 °C < ECT Temp. < 105.0 °C
|
Case2 | 1500rpm < engine speed < 4000rpm
35kg/h <mass air flow < 200kg/h
pressure quotient(PUT/AMP) <1.5
43.5mph < Vehicle speed < 81mph
Failure not detected for DTCs
|
Case3 | Time after start < 180 sec
change of IAT (between two measurements) <1.5 °C
change of AAT (between two measurements) <5.25 °C
engine off time > 450 min
ECT temp.(at engine start) - ECT temp.(at engine stop) > 40 °C
ECT temp. < 34 °C
Failure not detected for DTCs
|
Threshold Value | Case1 | measured AAT - modeled AAT <=-15 °C (hot engine)
|
Case2 | measured AAT - modeled AAT >= 15 °C (hot engine)
|
Case3 | measured AAT - modeled AAT >= 12 °C (cold engine)
|
Diagnostic Time | immediately
|
MIL On Condition | 2 Driving Cycles
|
Specification
Temperature(?/?) | Resistance(K?) | Temperature(?/?) | Resistance(K?) |
-20/-4 | 284.5 | 10/50 | 59.6 |
-10/14 | 164.2 | 30/86 | 24.18 |
0/32 | 97.5 | 50/122 | 10.8 |
Diagnostic Circuit Diagram
Signal Waveform & Data
Connect GDS with diagnostic connector.
Warm up the engine to normal engine temperature afte engine starts.
Select and monitor "Ambient Air Temperature sensor" parameter.
Fig.1) Parameter of "Ambinent Sensor" will be fixed at 20?(68?), if there is any fault in Ambient Sensor.
Is the ambient sensor abnormal ?
![]() | ? Go to "Inspection and Repair" procedure. |
![]() | ? This is a intermittent problem caused by poor contact of component or Control Unit ? Thoroughly check the looseness, poor connection, bent, corrison, contamination, deformation or damage of connector. ? Repair or replace as necessary and then, go to "Verification of Vehicle Repair" procedure. |