Circuit/System Description

The instrument panel cluster (IPC) applies 5 volts to the ambient air temperature sensor. The ambient air temperature sensor is a thermistor which varies in resistance as the temperature changes. As the resistance of the ambient air temperature sensor increases, the IPC senses a larger voltage drop across the sensor, indicating a lower temperature. As the resistance of the ambient air temperature sensor decreases, the IPC senses a smaller voltage drop across the sensor, indicating a higher temperature. The IPC is responsible for displaying the temperature and converting to degrees Fahrenheit if necessary.