Intake Air Temperature Sensor (IATS) is NTC thermister which voltage gets low if the temperature comes to be high. One is installed inside of MAFS and the other is installed between BPS and intercooler. It senses intake air temperature. In case of EURO-5 diesel engine, IATS is installed in front of turbocharger (inside of MAFS) and behind it (between BPS and intercooler). 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. (MAFS is needed for EGR FEED BACK control in electronically controlled diesel engine. The calculation of air density at certain temperature is required to perform EGR FEED BACK control correctly.)
In case of replacing MAFS, perform the "COMPONENT CHANGE ROUTINE" procedure with scan tool. If the "COMPONENT CHANGE ROUTINE" procedure has not completed until automatic learning completed, it may cause vehicle performance and exhaust gas problem.
P0113 is set when the voltage above 3200 mV - maximum output voltage of IATS - is detected for more than 1 sec. This code is due to 1) open or 2) short to battery in IATS signal circuit.
Item
Detecting Condition
Possible Cause
DTC Strategy
Voltage monitoring
IATS #1 circuit
IATS #1
Enable Conditions
IG key ON
Threshold Value
When output signal is above the maximum value. (above 3200 mV)
- Open in signal circuit.
- Short to battery in signal circuit.
Diagnostic Time
1 sec.
Fail Safe
Fuel cut
NO
Fixed at 50?.
EGR Off
YES
Fuel Limit
Check Lamp
ON
Temp.
- 40?
-20?
0?
20?
40?
60?
80?
Resistance
36.6~42.7K?
12.9~14.7K?
5.19~5.79K?
2.31~2.53K?
1.12~1.21K?
0.59~0.63K?
0.33~0.34K?