I have a 2004 Ford Explorer that the outside temperature gauge always reads inaccurately. If it matters, the temperature is always recorded as being well above the actual temperature of the air. This is not to be confused with the cars thermostat temp that reads accurately. I have checked fuses, and find myself at a loss for what the problem might be. Anyone have any clues?
I would check that the sensor is correctly mounted in front of the radiator and that the airflow through the radiator is not blocked. It is normal for the temperature to read too high for the first few miles after a warm restart or if the car has been sitting in the sun.