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

PCM turns on MIL. PCM substitutes outside air temperature for IAT. Transaxle shift adapts are maintained at current levels.

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. Checks shorted sensor or circuit No. 472 shorted to ground inside intake manifold. If PCM data PD05 stays at 147-151°C with sensor unplugged, circuit No. 472 is sorted to ground.
4. 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.

Fig 1: Code P037 Schematic, Shorted IAT Sensor

Courtesy of GENERAL MOTORS CORP.

Fig 2: Code P037 Diagnostic Flow Chart, Shorted IAT Sensor

Courtesy of GENERAL MOTORS CORP.