Circuit/System Description
WARNING: This page is about a different car, the 2019 Buick Cascada, 2018 Buick Cascada, and 2017 Buick Cascada. However, it is still accessible from the selected car via links, so may be relevant.
The air temperature sensors are a 2-wire negative temperature coefficient thermistor. The vehicle uses the following air temperature sensors:
- Air temperature sensor - left upper
- Air temperature sensor - left lower
- Air temperature sensor - right upper
- Air temperature sensor - right lower
- A/C evaporator temperature sensor
This sensor operates using signal and low reference circuits. As the air temperature surrounding the sensor increases, the sensor resistance decreases. The sensor is capable of reading temperatures ranging from -40 to +80°C (-40 to +176°F), with a signal voltage between 0 - 5 V. If the HVAC control module detects a malfunctioning sensor the software uses a default air temperature value. The default action ensures that the HVAC system can adjust the inside air temperature near the desired temperature until the condition is corrected.