I have a 2003 mustang
gt and i have an unusual problem that started recently. All of my lights (inside, panel, head lights) dim and return to normal irratically all at the same time but do not turn off, except my radio did once. I only notice it at idle. I thought the battery leads might have some corrosion build up that I didn't notice but it's relatively clean. I'm guessing it could either be the battery or the alternator is going bad. What do you all think?