Pcm Code P037 - Shorted Intake Air Temp (IAT) Sensor Signal: Notes
WARNING: This page is about a different car, the 1993 Cadillac Seville and 1993 Cadillac Eldorado. However, it is still accessible from the selected car via links, so may be relevant.
IAT sensor is a thermistor that varies its resistance with temperature. As sensor temperature increases, resistance decreases. High temperature will result in low signal voltage. PCM Code P037 sets when PCM sees an IAT sensor reading of 298°F (148°C) when coolant temperature is less than 212°F (100°C).