So, my 2000 Malibu 3.1 check engine light came on, dropped by my local Advance Auto Parts, turns out I'm getting a "IAT Sensor Circuit high voltage" code (sorry, can't remember the exact number, and don't have it with me).

Pulled the sensor, resistance went down as temperature went up. This should be correct fora thermistor, right? What should the voltage be on this circuit? What could cause the high voltage situation, if the sensor is working correctly?

Thanks in advance!!

 

The intake air temperature (IAT) sensor is a thermistor which measures the temperature of the air entering the engine. The Powertrain Control Module (PCM) applies 5.0volts through a pull up resistor. When the intake air is cold, the sensor resistance is high and the PCM will monitor a high signal voltage on the IAT sensor signal circuit. As the intake air warm, the sensor resistance becomes lower causing the PCM to monitor a lower voltage. If the PCM detects an excessively high IAT sensor signal voltage (low temperature indicated), DTCP0113 will set.