P0112

DIAGNOSTIC TROUBLE CODES P0112, P0113
Intake air temperature sensor, input to control module, open circuit or shorting to ground/batt+

Fault Symptom.
CHECK ENGINE lamp (MIL) on

Condition
In the case of an open circuit or short circuit, a diagnostic trouble code will be generated within 60 seconds at most

Diagnostic Procedure.
1. Check the operation of the temperature sensor using an ISAT scan tool.
Ignition switch in the ON position.
Select "READ FUNCTIONS".
Select "INTAKE AIR TEMP".
The Scan Tool should show the temperature of the intake air.

If the reading is OK, proceed to step 5.
If the reading is not OK, continue with step 2.

In the case of an open circuit, the Scan Tool will show about -70°C and in the case of shorting to ground it will show about +160°C.

2. Check the electrical interface in the temperature sensor's connector.
Unplug the 2-pin connector.
Ignition switch in the ON position.
Take voltage readings in the female connector:
- across pin 1 and the negative battery terminal ______ about 5 V.
- Across pin 2 and the positive battery terminal ______ about 12 V.

Measure the amperage (mA) in the female connector:
- across pins 1 and 2 ______ about 5 mA.

The measurements above are to show whether the ECM and the wiring as far as the temperature sensor are in good condition and functionally OK.

If all readings are OK, continue with step 3.
If any measured value is incorrect, continue with step 4.





3. The temperature sensor may be suspected of being faulty.
Check the temperature sensor's connector for corrosion and possibly remedy it.
Then check the resistance of the temperature sensor.
Take resistance readings in the temperature sensor's connector.
Nominal resistances are shown on table.





If the measured value is incorrect, fit a new the temperature sensor.
If the measured value is correct, continue with step 5.

4. Check The Wiring between the temperature sensor's 2-pin connector and the control module for continuity.
Check the leads for open circuit, shorting and possible stray currents.

If the measured values are correct, continue with step 5.

5. Clear the diagnostic trouble code and drive the car to see whether the DTC is generated again.

If the diagnostic trouble code is generated again, continue at "Procedure Before ECM Replacement". Component Tests
If the trouble code is not generated again the remedial measure taken was correct, otherwise the fault is of intermittent type.