Spent an evening the other week figuring out how to swap my digital thermometer from fahrenheit (yuck!) to Celsius (yay! Anders Celsius was Swedish, by the way). It works the other way around, too, so here goes:
Once you have the thermometer out of the dash (easy, a little wiggling does it) take it apart as much as possible. When you have it down to the state pictured, there should be a little blue plastic bit in the lower right hand corner. It is hard to see, but there is a tiny metal wire which is either hooked or unhooked. Changing its position swaps the thermometer back and forth from Celsius to Fahrenheit.
Hopefully this will help someone out! I have pictures, but apparently I don't have enough posts yet to do so.
Once you have the thermometer out of the dash (easy, a little wiggling does it) take it apart as much as possible. When you have it down to the state pictured, there should be a little blue plastic bit in the lower right hand corner. It is hard to see, but there is a tiny metal wire which is either hooked or unhooked. Changing its position swaps the thermometer back and forth from Celsius to Fahrenheit.
Hopefully this will help someone out! I have pictures, but apparently I don't have enough posts yet to do so.