P0113 — IAT sensor circuit — high input

Part of system: Electrical sensing & powertrain inputs

With P0113, prove the circuit before you condemn the part named in the scanner text. P0113 indicates the intake-air temperature sensor circuit is reading abnormally high voltage, which the ECM interprets as an impossibly cold or open-sensor condition depending on the sensor curve. With a wrong IAT, cold-start enrichment, fan strategy, and boost or EGR models drift, so the engine can feel lazy until fully warm. Check the IAT connector for corrosion, compare IAT PID to ambient with a known-good thermometer, and wiggle-test the harness near the airbox before replacing the sensor. Road salt intrusion into the MAF/IAT combo housing is a common winter failure. Discriminate among open circuit or high resistance in the IAT signal wire, corroded pins in the airbox or MAF/IAT connector, and failed thermistor inside the IAT or combo MAF sensor using voltage drop and connector integrity. Verify by compare IAT PID to a thermometer at the sensor tip, then measure signal and reference voltages against the wiring diagram; replace iAT sensor or integrated MAF/IAT unit only when the wiring path checks out clean.