The Ford Fiesta ambient temperature sensor is placed within the motive force's side footwell. Motors in hot or bloodless extremes would require appreciably greater attempt from the HVAC device to each cool and warmth the cabin of the car. Because of this</br> the system wishes to be privy to the temperature of the surroundings that the car is in. It's miles the activity of the ambient temperature sensor to measure the outside temperature of the vehicle as a reference factor for the pc to make calculations. When the ambient temperature sensor fails</br> the gadget does no longer have a reference factor from which to base its automatic calculations and the setting will now not paintings. Every other symptom of a bad or failing ambient temperature sensor is inconsistent cooling.