piqle

I have an 1999 Acura 2.3CL, one day my pedal stopper pad for the brakelights broke, and I had it replaced with a screw & nut. Ever since that happened I have a small battery drain from the fuse for my taillights & radio, I have an aftermarket radio but this hasn't started happening since the brakelights stayed on and killed my battery (the battery went bad, got a new one) and ever since then the battery will stay alive for a day up to sometimes a week, before dying again. I'm on my third battery now from them being drained until they're unchargable again. Can anyone help me with this? This is my first car, but I've done a small amount of mechanic work myself and would rather not have to bring it to a shop if it's a small fix that I can do myself.