Code P037, Shorted Intake Air Temperature (IAT) Sensor: Action

PCM turns on MIL. PCM substitutes 104°F (40°C) for IAT when engine coolant temperature is 104°F (40°C) or greater. PCM substitutes engine coolant temperature for IAT when engine coolant temperature is less than 104°F (40°C).

1. With a shorted IAT sensor, PCM parameter PD05 should indicate 148°C or greater. If PD05 does not indicate 148°C or greater, sensor is not shorted.
2. Checks for sensor short or circuit No. 472 shorted to ground. If PCM parameter PDO5 stays at 147-151°C with sensor unplugged, circuit is shorted to ground.
3. IAT sensors can be damaged by a backfire in intake. If vehicle has had more than one IAT sensor replaced, check for signs of backfire and high intake manifold temperatures due to improper valve train operation.
4. Fault is most likely at PCM connector or PCM. Before replacing PCM, check for damaged pins or poor connection.