BlaCkPlaGUE

lol

Trying to start my car in -25 degree celcius weather here, I have totally finished my fuel/intake system rebuild, and I've finally got my *** around to putting everything back in, and now I want to start it.
Battery was dead, so I charged it overnight and nothing, nothing at all. So today I pulled my dads battery out of his van and put it in, still nothing!
So I check out the main fuse box while the battery is still connected, and sure enoughe, the main fuse is blown, you can see that it is. So I try and pull it out, its stuck in there hardcore, so I get some pliers and start pulling.
The fuse starts breaking and ****, and then a nice blue spark pops from it and im like
goddamnit!
so I get the battery out of there and continue to rip this fuse out of the box. Im tugging at the main connectors (all the plastic is broken away now) and nothing, im like what the hell??? I figured that it was becuase it melted to the fuse box terminals..

Then I did a search. lol, apparently there are a couple screws that hold it in! I also searched some more and found that if any of the alt. wires are touching the engine, this can cause the main fuse to blow.

Do you think I fucked up anything when I got that small blue spark?
Are there any other things other than the alternator connections to see what caused the main fuse to blow.

thank you.

scathcart

If you fucked up anything, it'd be your battery.
By bridging your pliars across the fuse terminals, you effectively replace the fuse with a wire... and since your alt wire was touching the ground, you basically used your pliers to connect battery power straight to body ground... With the battery current available and the limited resistence in your circuit, you're lucky your didn't weld your pliars to the fuse box, heh.
Power will always take the shortest path to ground as possible... The alternator power wire connects to the firewall-side of the fuse box, while the battery power wire connects to the front-side of the fuse box, both connecting at the main fuse. With the alt connection touching ground, you sent battery positive directly to the fuse box, through the man fuse, and then straight to ground, which popped the fuse. When you used your pliars, you did the same thing only bypassing the fuse, so the only affected wires would be in that short-circuit, get it?

So... worst case scenario, you toasted your battery, but I doubt it, bad scenario: you melted the insulation on your power wires... best, and most likely scenario: you'll just need to replace the fuse and make sure the alt wire isn't touching ground when you reconnect it.


We've all done stupid things when it comes to power... I have seen guys place a wrench across the battery terminals and weld it in place. My personal best is cutting through live 347 V lines... now THAT makes a spark.


That said... replace the fuse... nothing should have gone wrong permanently as long as you didn't have the pliars brdiged for two long (could melt wires or, as stated before, destroy your battery)

RotaryEvolution

iTrader: (30)

yep, it is a straight shot to the battery, the fuse is actually to protect the alternator and wiring to it. replace the fuse, fix the wiring and you should be good.

Bob_The_Normal

yeah that one threw me for some confusion when I first got the car and jumped it the WRONG way.

And once I was so immersed in what I was doing with the master brake cylinder (I was changing it) that I set the 12mm craftsman wrench on, of all places... yep... the battery terminals. Now it's easy to spot the 12mm, it has a small melt mark on one side.

Took a good pull to get it off there fast too... lucky I was wearing those crappy little rubber gloves.

--Gary

BlaCkPlaGUE

Wow, thank you!

Well I bridged the connection for about half a sec, so im sure nothing bad happened. You have made it perfectly clear that its the alt wire. Now wich one, that big mother that comes off of it, or the green connector that fits in the back. Im assuming its the big one am I right?

I'll check it out most likely tues, day off, lots o time, hopefully a working car. heh.. thx

scathcart

It would be the big motha' that was touching the ground.

sleejay

i did the same thing when i first got my rx7 it didnt run so i found the main fuse fried, took me about 15 minutes to rip it to peices, until i noticed the (8mm?) bolt holding it in... lol

therotaryrocket

does the wire on the side of the alternator with the boot on it (charging positive?) go straight to the back side of the main fuse on that fuse box? Does the charging wire go anywhere else? my friends charging wire was corroded at the alternator terminal and also it was shorting to the engine hoist bracket, it made the voltage go waaay down and barely charge half the time.

scathcart

Yes

Yes, it pigtails off to a black female/male termincal connection and leads into the main body harness.