Circuit/System Testing: P0112

WARNING: This page is about a different variant/trim than selected.

With the ignition ON, the engine OFF, and the IAT sensor harness disconnected, observe the IAT Sensor parameter with a scan tool for a value of less than -39°C (-38°F).

If the IAT Sensor parameter is less than -39°C (-38°F), replace the IAT sensor.
If the IAT sensor parameter is more than -39°C (-38°F), test the IAT sensor signal circuit for a short to ground, low reference, or faulty ECM.

P0113

With the ignition ON, the engine OFF, and the IAT sensor harness disconnected, use a DMM and measure for a voltage range of 4.8-5.1 volts between the IAT signal circuit and a good ground.
- If the voltage is more than 5.1 volts, test the IAT signal circuit for a short to voltage.
- If the voltage is less than 4.8 volts, test the IAT signal circuit for an open, high resistance, or a faulty ECM.
Measure the voltage between the IAT low reference circuit and the IAT signal circuit.
- If the voltage is less than 4.8 volts, test the IAT low reference circuit for an open, high resistance, or a faulty ECM.
With the ignition ON, the engine OFF, and the IAT sensor harness disconnected, observe the scan tool IAT temperature parameter for a value of less than -39°C (-38°F).
With a 3-amp fused jumper wire connected between the signal and low reference circuits, observe the scan tool IAT temperature parameter for a value of more than 148°C (299°F).
- If the temperature is more than 148°C (299°F), test the IAT signal circuit for a short to a 5-volt reference circuit.
If the IAT sensor circuits test normal, replace the IAT sensor.