Hey everyone, new to the forums with an aggravating problem. I own a 2000 Impala with 135,000 miles on it. Yesterday I changed the MAF sensor then got in to test drive it but when I turned the key the only light that came on was the check engine light! There is no power to anything! No headlights, radio, other dash lights, or anything else. I tried jumping it with no results and the battery is only a month old anyway. I thought it might be the key fob battery and changed it with the same results. I'm completely dumbfounded and really need some help. Thank you