Intake Air Temperature
Intake air temperature (IAT) supplies the intake-air temperature used by the airmass model and available fuel and ignition corrections. Fit it where the selected airmass strategy expects the measurement; a post-heat-soak location can read hotter than the air reaching the cylinders.
Configuration and calibration
Open Sensors > IAT sensor. Assign Input channel and Pullup resistor, then enter three ascending temperatures and the corresponding sensor resistances (IAT dialog). The Common IAT Sensors selector offers GM, Miata, and Bosch presets, but the installed sensor and its data must match the preset.
Use the sensor manufacturer's NTC table to populate the three points. Enable Linear characteristic only when the supplied characteristic is intended to be linear and the first two points adequately describe it. Set the bias resistance from the board's input circuit, and use IAT sensor is pulldown instead of pullup only when the hardware requires that inversion. Verify Intake air temp against ambient before starting and observe Raw IAT while wiggle-testing the harness.
Wiring and diagnostics
Use a board-supported analog temperature input, sensor ground, and documented bias supply. The Universal 112 v1.2 pinout identifies its analog-temperature pins; pin locations and bias circuits are revision-specific. Follow the IAT datasheet for installation depth, thread/seal requirements, and acceptable environment.
Sensor Checker maps IAT timeout, low, and high faults to P0110, P0112, and P0113 (diagnostic mapping). A failed sensor also removes valid IAT-based correction and airmass input, so inspect the DTC and raw value rather than masking the effect in unrelated correction tables.
The IAT path feeds the charge-air calculation and the optional IAT fuel multiplier and IAT ignition correction. Correct the sensor before tuning either table.