4.
Monitor "AIR TERMPERATURE SENSOR" parameter on the GDS.
Specification : current intake air temperture is displayed.
Fig.1) Check if current temperature is same as the value displayed on the GDS.
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.)
P0097 is set when the voltage below 73mV(0.11V) - minimum output voltage of IATS(integrated with BPS) - is detected for more than 2.0 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 | ● Output signal below minimum value( below 73mV ) | |||
Diagnostic Time | ● 2.0 sec. | |||
Fail Safe | Fuel cut | NO | ● Intake Air Temperature sensor is fixed at 28℃. | |
EGR Off | NO | |||
Fuel Limit | NO | |||
Check Lamp | 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 |
Connect GDS to Data Link Connector (DLC).
Warm engine up to normal operating temperature.
Turn "OFF" electrical devices and A/C.
Monitor "AIR TERMPERATURE SENSOR" parameter on the GDS.
Specification : current intake air temperture is displayed.
Fig.1) Check if current temperature is same as the value displayed on the GDS.
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 BPS connector.
IG KEY "ON".
Check the voltage between signal terminal of IAT in BPS harness connector and chassis ground.
Secification : 4.8V~5.1V
Is the measured voltage within the specificaiton?
| ▶ Go to "Component Inspection". |
| ▶ Repair "2. Check short to ground in signal circuit" as follows. |
Check short to ground in signal circuit
IG KEY "OFF", ENGINE "OFF".
Disconnect BPS connector and ECM connector.
Check continuity between signal terminal of IAT in BPS harness connector and and chassis ground.
Specification : Discontinuity(Infinite Ω)
Is the measured resistance within the specification?
| ▶ Go to"Component Inspection". |
| ▶ Repair short to ground in signal circuit and go to "Verification of Vehicle Repair". |
IG KEY "OFF", ENGINE "OFF".
Disconnect BPS connector.
Measure resistance between signal terminal of IAT in BPS connector and ground terminal of BPS connector (component side)
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 Repair". |
| ▶ Replace BPS 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. |
