When i picked up my 2002 yukon 2 weeks ago it was in the 20s outside, My question is if you push the a/c button on it flashed off and on. Is this normal due to the temp. Now its in the 50s and the light stays lit. The salesman had no idea and I havnt had time to bring it in to service. I know on all my other cars the a/c button stayed lit if pusshed no matter how cold out.