Help!!Erratic behavior

I have a 1999 Grand AM 3.4 that I inherited from my brother. He put some mods on it, including undercarriage lights. So, I know he fooled around with factory wiring. Here is the problem, my car a moments, like stopping or hitting a bump or quick turn, the radio pauses for a fraction of a second. It will also do this when you take step on the brake some times. It also does this when I push on the brake and take the car out of park and put it into reserve or drive sometimes. I have had the battery and the alternator checked and they were fins. It drives me crazy and wonder if it is a symptom of a much larger issue.

Hey phaderus. Sound like a short to me. Has the radio or is the radio an aftermarket? I would find out what exactly the prevous owner did when installing the lights. If they hacked into some wires, it could short out and start a fire somewhere and thats no fun :( Just the radio messes up?

It is an aftermarket radio. I inheriated this car when my teen age brother died. I am not quite sure what he did to electronically. He put light underneath the car. He put on one of those aftermarket kits on the Instruement panel. The weird thing is the way it does when I am in park and I change gears.

i'd say its probley a short. You can look under the car and see if there are any wires hanging loose. Follow the wiring from the lights below and see if maybe a wires loose or came un-connected. The radio could be wired onto one of the ground wires for something else. May need the help of the professionals on this one...

A short will most likely blow a fuse.
It sounds like you have a bad connection in the wiring to the radio causing an intermittant open.
Check the wiring closely..it was probally wired with butt connectors and one of the connectors has a bad crimp

Thanks for the suggestion! I will follow your advice and try to fix the problem.

I own a 2000 Grand Am GT and my car does the same thing when i touch the brake. If i blinker my lights act weird, and my car has even dies on my while driving, and the sometime it will not start. When i try to start it I get absolutly nothing. I have to unhook the battery and hook it back up and then it acts fine for a little bit. I have had a new battery and it checked and also my alternator. I have no idea what is wrong wondering if u could help.
Thanks
lisamd