We have at least two threads running on this, but I will do the belt-and-braces thing here:
Sometimes when the AC is off, I push the AC button, it won't light and turn on the cold.
Sometimes when the AC is on, I push the AC button, it won't tun OFF the light and turn OFF the cold. When this happens, turning off the blower always kills the blue light and the cold.
Phil Ethier Minnesota USA
1973 Triumph Stag LE22439UBW "uncle jack", Sapphire Blue
2004 Suburban 8.1, Sport Red
2005 Lotus Elise, Bordeaux Red Pearl
2017 Ford Fusion (wife had to stop driving manual due to shoulder problem), Oxford White.
2006 Gulf Stream Conquest Super C