3.
Is the problem found?
 | ▶ Repair the trouble causing part and go to "Verification of Vehicle Repair". |
 | ▶ Go to "Signal Circuit Inspection ". |
Intake Air Temperature Sensor(IATS) is NTC thermistor. Installed inside of both MAFS and BPS, it senses intake air temperature.
In case of EURO-4 diesel engine, IATS is installed in front of turbocharger(inside of MAFS) 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.(MAFS 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.)
P0113 is set when the voltage above 4886mV - maximum output voltage of IATS - is detected for more than 1.0 sec. This code is due to 1) open or 2) short to ground or 3) short to battery 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 above the maximum value ( above 3.200mV ) | |||
Diagnostic Time | ● 1 sec. | |||
Fail Safe | Fuel cut | NO | ● Intake air temperature is regarded as 50℃ | |
EGR Off | NO | |||
Fuel Limit | NO | |||
MIL | NO | |||
Temp. | - 40℃ | -20℃ | 0℃ | 20℃ |
Resistance | 35.14~43.76KΩ | 12.66~15.12KΩ | 5.12~5.89KΩ | 2.29~2.55KΩ |
Temp. | 40℃ | 60℃ | 80℃ | |
Resistance | 1.10~1.24KΩ | 0.57~0.65KΩ | 0.31~0.37KΩ |
Electrical systems consist of a lot of harness and connectors, poor connection of terminals can cause various problems and damge of component.
Perform checking procedure as follows.
Check damage of harness and terminals : Check terminals for contact resistance, corrosion and deformation.
Check connecting condition of ECM and component connector : Check terminal seperation, damage of locking device and connecting condition between terminal and wiring.
Disconnect the pin which requires checking at male connector and insert it to the terminal at female connector for checking connecting condition. ( after checking, reconnect the pin at correct position. )
Is the problem found?
| ▶ Repair the trouble causing part and go to "Verification of Vehicle Repair". |
| ▶ Go to "Signal Circuit Inspection ". |
Check signal circuit voltage
IG KEY "OFF", ENGINE "OFF".
Disconnect IATS connector.
IG KEY "ON".
Measure the voltage between signal terminal of MAFS harness connector and chassis ground.
Specification : 4.8V~5.1V
Is the measured voltage within the specification?
| ▶ Go to "Component Inspection". |
| ▶ Go to "2.Check open in signal circuit" as follows. |
Check open in signal circuit
IG KEY "OFF", ENGINE "OFF".
Disconnect MAFS connector and ECM connector.
Check continuity between signal terminal of MAFS harness connector and ECM harness connector.
Specification : Continuity (below 1.0Ω)
Is the measured resistance within the specification?
| ▶ Go to "3.Check short to battery in signal circuit " as follows. |
| ▶ Repair open spots in signal circuit and go to "Verification of Vehicle Repair". |
Check short to battery in signal circuit
IG KEY "OFF", ENGINE "OFF".
Disconnect MAFS connector and ECM connector.
IG KEY "ON".
Measure the voltage between signal terminal of MAFS harness connector and chassis ground.
Specification : 0.0V~0.1V
Is abnormal voltage detected in the circuit with both connector disconnected?
| ▶ Repair short to battery and go to "Verification of Vehicle Repair". |
| ▶ Go to "Ground Circuit Inspection". |
IG KEY "OFF", ENGINE "OFF".
Disconnect MAFS connector and ECM connector.
IG KEY "ON".
Measure the voltage between signal terminal of MAFS harness connector and chassis ground. [ TEST "A" ]
Measure the voltage between signal terminal and groud terminal of MAFS harness connector. [ TEST "B" ]
( Signal terminal : Check + prove , Ground terminal 2 : Check - prove )
Specification : the voltage difference between TEST "A" and TEST "B" is within 200mV
Is the measured voltage within the specification?
| ▶ Go to "Component Inspection". |
| ▶ When "B" voltage is not detected : Repair open in ground circuit and go to "Verification of Vehicle Repair". ▶ When the voltage difference between "A" and "B" is above 200mV : Eliminate the causes of excessive resistance and go to "Verification of Vehicle Repair". |
IG KEY "OFF", ENGINE "OFF".
Disconnect MAFS connector.
Measure resistance between signal terminal and ground terminal of MAFS component.
Specification : Refer to Specification of General Information.
Is the measured resistance at certain temperature within the specified resisance range at the temperature?
| ▶ Go to "Verification of Vehicle Rapair". |
| ▶ Replace MAFS ASSY' and go to "Verification of Vehicle Repair". |
After a repair, it is essential to verify that the fault is corrected.
After connecting GDS select "Diagnostic Trouble Codes(DTCs)" mode to and then clear DTC.
Drive the vehicle within DTC Enable conditions in General information.
After selecting "Diagnostic Trouble Codes(DTCs)" mode and check DTC is recorded again.
Are any DTCs recorded ?
| ▶ Go to the DTC guide of recorded NO. in GDS. |
| ▶ System operates within specification. |
