Code Definition

P0112 — Intake Air Temperature Circuit Low Input

System: Powertrain  |  Type: Generic (OBD-II Standard)  |  Make: Generic

About P0112

P0112 is a generic (obd-ii standard) powertrain diagnostic trouble code. It belongs to the P-prefix family of codes, which covers engine, transmission, emissions, or fuel-system faults.

When P0112 is stored, the module has detected a signal or supply voltage lower than the expected operating range.

Scanning & clearing: A generic OBD-II scan tool will usually read and clear powertrain (P) codes. For live data, freeze-frame capture, and bi-directional tests you may need a more capable scan tool that supports the vehicle's ECM protocol.

Because P0112 is a generic OBD-II code, its base definition is shared across manufacturers. The specific diagnostic steps, reference values, and repair procedures can vary by vehicle, and the TaT Diagnostic Assistant includes verified procedures submitted by working technicians.

Code Information

The intake air temperature sensor is a negative temperature coefficient thermistor monitored by the ECM through a pull up resistor, so its resistance and therefore its signal voltage fall as intake air temperature rises. The ECM uses this reading to calculate air density, trim fuel delivery, adjust ignition timing, and manage knock protection and idle strategy. P0112 sets when signal voltage drops below the lower threshold for a calibrated period, which corresponds to an implausibly high indicated air temperature and normally means the signal circuit is shorted to ground or the sensor has fail...

Join TaT to view the complete code information and diagnostic details.

Quick Facts