Is the ambient air temp sensor built into all Mazda 3's? Just curious because when I had my stock radio in, the AMB temp would come on the screen every now and then, but would only show 3 dashes. At 1 time, it would show 2 or 3 dashes and the Celsius indicator, but would never show the actual temp. I didn't know if this was a malfunction of the radio, or the AMB temp sensor.