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 298°F (148°C) or greater. If PD05 does not indicate 298°F (148°C) or greater, sensor is not shorted. See NOTE ON INTERMITTENTS.
2. Checks for sensor short or circuit No. 472 shorted to ground. If PCM parameter PDO5 stays at 148-151°C with sensor unplugged, circuit No. 472 is shorted to ground.
3. IAT sensors can be damaged by a backfire in intake manifold. If vehicle has had more than one IAT sensor replaced, check for signs of backfire or 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.