P0110

DIAGNOSTIC TROUBLE CODES P0110, P0112, P0113
Intake air temperature sensor, malfunctioning or not working at all

Fault symptom
The CHECK ENGINE lamp (MIL) is on.

Conditions.
If there is a short circuit/open circuit, a DTC will be generated after 5 seconds.


DIAGNOSTIC PROCEDURE

1. Checking the operation of the temperature sensor.
Connect a Scan Tool.
Ignition switch in the ON position.
Select "READ FUNCTIONS".
Select "INTAKE AIR TEMP".
The Scan Tool shows the temperature of the intake manifold.

NOTE: In the event of an internal temperature sensor fault, the control module will assume the default value of 8°C. This is the figure that the Scan Tool will display in such cases.

If the reading is OK, continue with point 4.

If the reading is not OK, continue with point 2.






2. Checking the electrical interfaces of the temperature sensor.
Turn the ignition switch to the ON position and then back to the OFF position. Unplug the temperature sensor's 2-pin connector.
Take voltage readings at the connector across:
- Pin 2 and battery negative about 5 V
- Battery positive and pin 1 about 12 V.


Check the control module's temperature input for continuity.
- Select "READ FUNCTIONS".
- Select "INTAKE AIR TEMP".

The Scan Tool should show a reading of about -40°C.
Connect a jumper lead across pins 1 and 2 of the temperature sensor connector.
The Scan Tool should show a reading of about +125°C.
The above tests show whether the control module and wiring as far as the temperature sensor are in good working order.

If all test readings are OK, change the temperature sensor.

If any test reading is not OK, continue with point 3.







3. Checking the wiring harness.
Check The Wiring between the control module and the temperature sensor's 2-pin connector for continuity.
Check The Wiring harness for continuity, shorting and any stray currents.

If the wiring is OK, continue with point 4.

If any lead is not OK, rectify the fault.

4. Final Check
Clear the diagnostic trouble code, drive the car on test and check whether the trouble code is generated afresh.

If the DTC is generated again, refer to Before Replacing A Control Module.

If the DTC is not generated again, the action taken to rectify the fault was correct, otherwise the fault is of intermittent nature.