I noticed that w/in the first week of my purchase. Went back to the dealer. It is apparantly a GM thing as it exists on Cadilac too.

It is a nice feature for me, but I don't see the need for the A/C button if this is doing the same thing.

That said though, it acts like a Maxx A/c switch on the H3 like Ford has to give a faster fan speed when you select maxx a/c from reg a/c.