RX7SUZY

Hi all, I really needs some advice here.

We had heavy rain yesterday and I was driving my 90 convertible. I was parked in a parking lot, got in and started the car. When I press on the brake I hear a "thump" from the subwoofer. Thought that was strange, but didn't think anything of it. After that, whenever I would step on the brake I'd get the thump and the head unit would lose power, as soon as I let up on the brake, its back.

Drove home and got off the highway and stopped at the top of the ramp and the car completely shut off and all the idiot lights were on. Tried to restart it and nothing, key turned but no spark. waited a minute and tried again and it was fine, to get home. I figured maybe something got wet and caused it.

Go out this morning and still, whenever I step on the brake the sub goes thump (like a bass note) and the head unit turns off, let up on the brake, music's back!

Got to work and went to turn off the headlights and the stereo did the same thing. so now its when you step on the brake, or turn on/off the headlights I lose electrical to the stereo.

I'm kinda afraid at this point to drive the car home, what if I press on the brake and lose something important?

please help!!
Suzy
sabbott@emon.com

Grappler

iTrader: (6)

From what it sounds like you might have a short or your alternator could be going I remember when mine went my stereo would go out all the time.

My alternator would run for about 10 min then stop for 10 minutes which could cause a few of the symptoms you are describing.

First I would check your wiring then test the output of your alternator and go from there.

pfsantos

iTrader: (1)

Definitely sounds like the extra (electrical) load from the brake lights or headlights is causing havoc on a weak charging system. What's the voltmeter showing when you step on the brake or turn on the headlights? Another heavy load is the defroster. Try that and see if you get the same symptoms.

I would hook up booster cables from another car to yours, start both cars. Then have all the electrical loads off on the good car, and try the brake and lights on your car. The good car's charging system should support your car's needs and the problem should go away. If it does, you've found the problem.

Let me know if you follow...

RX7SUZY

I'm taking it to my mechanic tonight, I forgot about the brake lights pulling the extra load when hitting the brakes. I'll print your replies and take it with me tonight when I drop it off.

The high beam switch died about a month ago so I have to get that fixed for inspection next month anyway.

I hope that its the alternator and not a short, I know these gremlins are a bitch to find and I hate for him to spend hours tracking it down. If it was something where I was hitting a bump and wires were moving/giggling and the stereo went out I'd be more inclined to think a short, but when sitting in a parking spot and press the brakes...or turn on the headlights its gone.

Its got 67K miles on it, the previous owner rebuilt the engine at 50K but I don't know if he did the alternator when he did the rebuild.

Thanks again!!
Suzy