First, the story:
So I put in a sub and an amp. The amp is running 400W RMS @ 2 Ohms x 1 (mono). The amp is located where the spare tire used to sit and I ran everything just as suggested in darkknight's thread.
So I got all this done on Saturday. Worked perfectly for 2-3 days. Had a LONG road trip so I know it was exposed to a lot of use and high heat, and yet it still performed normally.

So Monday I'm in the city headed home and the car shuts off. I think "Oh shit...". I start to pull over and smoke starts pouring out of the hood and out the AC vents.

I jump out and pop the hood as fast as possible, only to see something I have NEVER seen/heard of. The negative battery post had MELTED.


Here are the pics:

http://s22.photobucket.com/albums/b333/W1l...nt=DSC00351.jpg
http://s22.photobucket.com/albums/b333/W1l...nt=DSC00354.jpg
http://s22.photobucket.com/albums/b333/W1l...nt=DSC00355.jpg
http://s22.photobucket.com/albums/b333/W1l...nt=DSC00356.jpg
http://s22.photobucket.com/albums/b333/W1l...nt=DSC00358.jpg

You can clearly see the melted metal on top of the battery and some of the post gone due to being melted off.

Now, I am 99% sure this was caused by my own faulty amp wiring, but I am not 100% sure to specifically what/how it happened.

My best guess: I was being cheap and had an old fuse from my old setup that had small gauge (12 or smaller) running through it (the rest of the power wire was 4 gauge), so I connected the rest of the power wire to one end of that which ran through the fuse and out still in the same (smaller) gauge and to the battery. I THINK this wiring must have overheated and melted or something and touched something in the engine bay that was grounded, causing this whole fiasco. The reason I think this, is because I jiggled the power wire and saw it spark off a metal box (no idea what it is/does) on the driver's side of the battery.

Does this sound plausible? Any other ideas as to what could have caused this?
How do I fix this problem so it doesn't happen again? Maybe I just need to stop using crappy, small gauge wire, and get something heavier to use with the rest of the 4 gauge I used?

Btw, the car is at the dealer right now having the battery and ground wires replaced.

Please help. I'm desperate here.

Thanks,
-Will

 

hm, everytime i've seen something like that it's due to an arc created from a power wire touching a ground (e.g., when a wrench is laid on both + and - terminals)

 

if you have seen sparks jumping from your power wire to ground (any
metal part of the car) you know you have a short there.
probably what happened is that the inadequately-sized section of power
wire got hot and melted it's insulation, then grounded, causing way too
much current to flow, heating up the ground wire so its insulation melted,
and the battery so its post melted.
the way to make sure it doesn't happen again is to replace any wire with
bad insulation, make sure all the wires are capable of carrying the current
you're drawing (4ga is fine), and make sure your fuse is as close to the
battery end of the power wire as possible, and is an appropriately-sized
fuse, ideally just above the maximum current your amp can draw.

 

Yeah I figured that was the problem, and thats what I plan on doing to fix it. Just making sure no one else had any differing opinions before I go ahead and do it.

 

Where and what size is the fuse on your power wire?

 

It was a 40A fuse. I don't think the fuse was the main problem though. I think it was the crappy, small gauge wiring running in/out of the fuse and to the battery that caused the problem.

 

Is the fuse right at the battery, or by the amp. A melted ground is the sign of a serious short. I'm willing to bet your power wire is short to ground. You're lucky the car didn't burn to the ground. The ground wire has to get cherry red to bubble insulation like that.