Common Symptoms
- Check Engine Light illuminated
- Incorrect temperature display on instrument cluster
- HVAC system may not operate correctly
- Engine cooling fans run continuously or not at all
- Poor cold start performance in some vehicles
Most Likely Root Causes
- Damaged or corroded ambient air temperature sensor wiring
- Failed ambient air temperature sensor
- Shorted sensor circuit to power
- Water intrusion or corrosion at sensor connector
- Faulty engine control module
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Component Location
Ambient air temperature sensor is typically mounted behind the front bumper or grille area where it can measure outside air temperature.
Manufacturer Notes
Some manufacturers use this sensor input for HVAC control and fuel trim calculations during cold start conditions.
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