DTC P0507: Idle Control System Rpm - More Than Expected: Notes
WARNING: This page is about a different car, the 2003 Mazda 6. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
If ambient pressure is 21.3 in. Hg (72.2 kPa) or less or intake air temperature is 14°F (-10°C) or less, PCM cancels DTC P0507.