he Intake Air Temperature Sensor (IATS) is installed into the Mass Air Flow Sensor (MAFS). The IATS uses a thermistor whose resistance changes with the temperature. The electrical resistance of the IATS decreases as the temperature increases, and increases as the temperature decreases. The 5 V power source in the ECM is supplied to the IATS via a resistor in the ECM. That is, the resistor in the ECM and the thermistor in the IATS are connected in series. When the resistance value of the thermistor in IATS changes according to the intake air temperature, the signal voltage also changes. Using this signal, the information of the intake air temperature, the ECM corrects basic fuel injection duration and ignition timing.
If measured temperature is lower than the maximum threshold value during 1sec, ECM sets DTC P0112.(In this case, the input signal voltage is the minimum threshold vaue.)
Item | Detecting Condition | Possible Cause |
DTC Strategy |
•
Signal check, low |
•
Poor Connection
•
Short to ground in signal circuit
•
IATS |
Enable Conditions |
•
ECT > 70C
•
Air mass < 32kg/h
•
Vehicle speed < 7mph | |
Threshold value |
•
Intake air temperature sensor's voltage < 0.122V | |
Diagnosis Time |
•
1 sec | |
MIL On Condition |
•
2 Driving Cycles |
Temp. (℃) | Resistance (kΩ) | Temp. (℃) | Resistance (kΩ) |
-40 | 95.95 ~ 105.78 | 20 | 3.42 ~ 3.61 |
-20 | 27.4 ~ 29.77 | 40 | 1.43 ~ 1.5 |
0 | 9.08 ~ 9.72 | 60 | 0.66 ~ 0.69 |
10 | 5.49 ~ 5.83 | 80 | 0.33 ~ 0.34 |
