In real need of electrical help!!!

Oct 12, 2006
141
0
16
Chicago, IL
Ok, to start off, I made a pretty big mistake. I don't have any power to anything in my car right now, and I can't figure out why. Here is the back story... I was loosening the bolt on the alternator that is the swivel arm for the alternator. I forgot to disconnect the negative battery cable before I did. So while I was loosening the bolt, I dropped my wrench and it was still connected to the nut, spun down and landed on the positive terminal for the alternator. There was a big spark, and now I have no power. I am terrible with electrical problems, so I was wondering, where do I start? What are the right steps to take to figure out my problem? I checked all of the fuses already and none appear to be bad. I checked the main circuit breaker and reset it. I got my alternator tested and it failed, so I bought a new one and installed it already. So my two main questions are, where to start? and how do I test relays to see if they are good or not?
 

SupraMan1987

New Member
Mar 8, 2006
258
0
0
34
Hickory area, NC
You most likely arced the battery off and cooked it. Have you had the battery tested? I've accidentally hit both terminals before and it did no damage, but your battery could of been in worse health than mine was at the time.
 

Moy

It's broken...
Aug 6, 2008
2,432
0
36
Beach Park, IL
I would have the battery tested for sure.

If your wrench landed on both the positive and negative terminals, well... your lucky the battery didn't explode. That would have sucked really really bad
 

jetjock

creepy-ass cracka
Jul 11, 2005
9,439
0
0
Redacted per Title 18 USC Section 798
Either the alt or main fusible link is blown. Most likely the alt. Best to measure them. When working with electricity you can't always go by appearance because it's typically invisible...though I've felt it's presence on a number of occasions ;)
 

lewis15498

Don't blame ebay cheapass
Sep 28, 2008
1,397
1
0
Raynham, Massachusetts, United States
You need a new flux capacitor thats all.

no, that usually kills the alternator, and like jetjock said you likely blew either the main or alt fusable link, replace that before a battery cuz its cheaper, but you may have damaged the battery too.
 
Oct 12, 2006
141
0
16
Chicago, IL
jetjock;1348936 said:
Either the alt or main fusible link is blown. Most likely the alt. Best to measure them. When working with electricity you can't always go by appearance because it's typically invisible...though I've felt it's presence on a number of occasions ;)

Where exactly are both of those fusible links? I know of the black one in the main fuse box under the hood, which fusible link is that? And I didn't arc the battery directly, I arced the terminal on the alternator to ground.
 

hvyman

Dang Dude! No Way Man.
Staff member
Apr 17, 2007
12,568
1
0
Fullerton,CA
same thing when you ground power with no load you'll blow the fuse and if there is no fuse you'll fry the wiring. check in the fuses under the hood.
 

mkIIIman089

Supramania Contributor
Mar 30, 2005
3,061
0
36
Ohio
Quick Red Head;1348992 said:
Where exactly are both of those fusible links? I know of the black one in the main fuse box under the hood, which fusible link is that? And I didn't arc the battery directly, I arced the terminal on the alternator to ground.
Probably likely you blew the 100A Alt fusible link. It's in the fuse box in the engine bay - bolted in.
 

Asterix

Lurker of Power
Mar 31, 2005
469
36
28
Vienna, VA
Shorting a big lead acid battery briefly won't hurt the battery. They're pretty tough. Shorting it long enough to discharge it completely may hurt it.

I wouldn't worry about the battery. Something else let go, probably because it was supposed to, thus saving your wiring. Fuses protect the wiring.

Asterix
 

Hmong_1G

Name the Place and time.
Dec 31, 2008
280
0
0
California
Trace your alternator wirings too. The wire might look good on the outside, but internally it could be toasted (literally :aigo:). I say fusable links first.
 
Oct 12, 2006
141
0
16
Chicago, IL
The fusible link in the fuse box under the hood is fine, no sign of being burned or anything. Does anyone know how to test the main power relay and other relays to see if they are working properly?
 
Oct 12, 2006
141
0
16
Chicago, IL
jetjock;1349298 said:
Look here:

http://www.cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?S=Main&P=18


Pull out the headlight relay and jumper pins 4 and 5 together with a paper clip. Turn on the headlight switch. They won't come up but do they come on?

Do you have a meter?

I have that website bookmarked, I just have no idea about anything electrical, so me reading it doesn't help much, lol. But, yes I do have a meter, my headlights are already up because they were when I was working on it, and can I use a piece of wire instead of the paperclip?
 

HommerSimpson

New Member
Dec 31, 2007
1,067
0
0
New Smyrna Beach Florida
Im sure it has pictures to.. so you should look... You will need to UNBOLT the fuse box.. the one by the alt... you will see some wires that if memory serves me right.. look brown or black.. like they have been heat shrinked... those are the fusable links... but you gota unbolt the fuse box to see them...
 
Oct 12, 2006
141
0
16
Chicago, IL
Well, I know of the fusible link in the main fuse box that bolts in, I have had to replace that before. When I bought the car, it was bare wire that was barely touching together it was so short. On electrical wiring diagrams, it shows another fusable link before that one, and I was wondering what that one looked like b/c I can't seem to find it.
 
Oct 12, 2006
141
0
16
Chicago, IL
jetjock;1350508 said:
The the main FL is bad or the battery connections are bad. That's assuming the battery is good, which it ought to be. Easy enough to check...

For the main FL, is that the ALT one in the main fuse box under the hood?