Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Ambient Air Temperature Sensor
The ambient air temperature sensor is a 2-wire negative temperature co-efficient thermistor. The vehicle uses the following air temperature sensors:
- Ambient
- Inside
A 5-volt reference and signal circuit enables the sensor to operate. As the air temperature surrounding the sensor increases, the sensor resistance decreases.
The sensor operates within a temperature range of -40°C (-40°F) to 60°C (140°F). The HVAC control module receives a class 2 message from the instrument panel cluster (IPC). The ambient air temperature sensor is mounted in the forward engine area of the vehicle. In this position, it is exposed to the airflow through the grill before it reaches the radiators. The sensor signal varies between 0 to 5 volts. The HVAC control module converts the signal to a working temperature range.
If the HVAC control module detects a faulty class 2 signal, then the control module software will use a defaulted air temperature value.
The default action ensures that the HVAC system can adjust the inside air temperature near the desired temperature until the system is fixed.
The ambient air temperature is updated and displayed under the following conditions:
NO RELATED
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.