Intake Air Temperature Sensor(IATS) is NTC thermistor. Installed inside of both AFS and BPS, it senses intake air temperature.
In case of EURO-4 diesel engine, IATS is installed in front of turbocharger(inside of AFS) and behind it(inside of BPS). Comparing air temperature from both sensors(one is intake air temperature, the other is air temperature passing through turbo charger), more accurate sensing of intake air temperature is possible.
With intake air temperature signal, ECM performs EGR control correction and fuel injection quantity correction.(AFS is needed for EGR FEED BACK control in electronically controlled diesel engine. The calculation of air density at certain temperture is required to perform EGR FEED BACK control correctly.)
P0112 is set when the voltage below 73mV - minimum output voltage of IATS(inside of AFS) - is detected for more than 1 sec. This code is due to short to ground in IATS signal circuit.
Item | Detecting Condition | Possible Cause | |
DTC Strategy | ● Voltage monitoring | ● IATS circuit ● IATS component | |
Enable Conditions | ● IG KEY "ON" | ||
Threshold Value | ● When output signal is below the minimum value ( below 0.073V ) | ||
Diagnostic Time | ● 1 sec. | ||
Fail Safe | Fuel Cut | NO | ● Intake air temperature is considered as 20℃ |
EGR Off | NO | ||
Fuel Limit | NO | ||
Check Lamp | NO |
Temperature | - 40℃ | - 20℃ | 0℃ | 20℃ | 40℃ | 60℃ | 80℃ |
Resistance | 35.14~43.76KΩ | 12.66~15.12KΩ | 5.12~5.89KΩ | 2.29~2.55KΩ | 1.10~1.24KΩ | 0.57~0.65KΩ | 0.31~0.37KΩ |
