Circuit Description
The body control module (BCM) monitors the outside air temperature sensor to display outside air temperature. The temperature sensor is a 2-wire negative temperature co-efficient thermistor. The BCM applies 5 volts to an internal input resistor that is connected to the signal circuits of the Outside air temperature sensor. The BCM provides the ground to the outside air temperature sensor through the low reference circuit. The BCM monitors the voltage drop across the Outside air temperature sensor and uses the input for automatic control calculations. When the outside air temperatures are cold, the resistance of the sensors are high and the voltage signals are high. When the air temperatures are hot, the resistance of the sensors are low and the voltage signals are low. The BCM converts the voltage value to a temperature value of Celsius and Fahrenheit to be displayed by the driver information center (DIC).