Alright, I'm driving my 96 Z24, hit a bump. Most the time what happens is ABS, Parking Brake, and Coolant Level warning light come on, but also the cd player cuts out, and the air seems like i turn it down to the lowest setting even though its on highest speed. Also the gear indicator on the cluster dims out, and the gauges drop like the car was shut off. Also in worse case i hear all kinds of relays clicking on and off. I don't understand what is doing this. Yesterday i swapped out head units, took off my strut bars, and swapped wheels. Other then that nothing has changed. I took out the head unit and wiring adapter and drove and it still did it, then took out the screws for hvac and moved it around making sure wire just wasn't pinched somewhere, didn't fix it. When i took off the Top Terminal Adapter for my sub i thought maybe the post was shorting out on hood so i put the little plastic cap back over it and didn't fix it.
I'm out of ideas honestly. it just seemed like a loose connection or short but i can think of where at, so im posting see if anyone else has similar experience and what they found out. sucks too because the car was to be sold this weekend..
I had an '87 s-10 blazer did the same thing. There was a common ground wire for the entire dash located at the right bottom bolt that held the dash in. I don't know if your car is wired the same but that's where I'd start.
Check your battery cables.. Possibly loose or corroded...
Under the battery tray, there's a ground on the frame rail.