Electrical Problems!!!

[slightly_red_MA70]

So my alternator decided it was going to die on me and start overcharging. First off, it blew up the capacitor for my stereo in my trunk and lit my trunk on fire....then yesterday it decided that it was gunna light the fuse box in the engine bay on fire, ended up blowing 10 different fuses, 4 tail lights, one front turn signal, a couple dash lights, and my air/fuel ratio guage. I looked into the fuse box and in the spot labeled "ALT 1.25B" there is a WIRE!!!!

Is there not supposed to be a fuse there!!? If someone could supply me with a picture of the fuse box that would be great.

Anyways, i bought a new alternator and some fuses today...install everything(put a wire back in that spot just for now:3d_frown, car runs "good" until i go for a little drive...starts overcharging again but no battery light this time like before. It sometimes holds steady at 18V and sometimes drops down to normal voltage. It could just be my guage? Or something to do with that wire? Or another faulty alternator?

Any help would be great. Thx


UPDATE:The volts are steady at 18V while driving and they only drop down to normal when i put in the clutch/come to a stop and idle. All the lights go bright but theres still no battery warning light coming on

 

[Poodles]

As you have a pre-89, the wire fusible link is stock (it was changed on later models).

Beyond that, it's out of my knowledge...

 

[slightly_red_MA70]

As you have a pre-89, the wire fusible link is stock (it was changed on later models).

Beyond that, it's out of my knowledge...

So what you telling me is that its supposed to be a wire in my fues box not a fuse?

 

[88_7mge]

nooooo...its not just any wire. Its a fusible link. Go to Toyota and tell them you need a fusible link for the alternator circuit for your car. A regular piece of wire in its spot is a foolish thing to do as it runs the possibility of starting another fire.

As far as your charging issue goes, if you want to rule out your gauge the best thing you can do is check battery voltage with a volt meter while the gauge is reading high. best bet for doing that quickly and easily would be to get something to plug into your cigarette lighter outlet on the dash, cut the wires and have someone measure voltage off there while you drive. *please dont try to check it yourself while driving your car*

if its an actual problem with it overcharging hit it back up on here and ill try to think of what would cause it to overcharge.

What brand alternator did you throw on the car?

 

[slightly_red_MA70]

What brand alternator did you throw on the car?

No idea, its a rebuilt from Fortins. I had a bosch on it before

EDIT:Volts go up to 18V on the guage while idling now, when i turn the headlights on it goes back down to 12V.
Did the test...Overcharging when guage says 18V at idle/driving, Low charge while idling with headlights on guage shows 12V.

 

[88_7mge]

No idea, its a rebuilt from Fortins. I had a bosch on it before

EDIT:Volts go up to 18V on the guage while idling now, when i turn the headlights on it goes back down to 12V.
Did the test...Overcharging when guage says 18V at idle/driving, Low charge while idling with headlights on guage shows 12V.

Sounds to me like your voltage regulator is bad. The only way you would be getting 18volts out of it is if it was going full field. Take the alternator back and get another one and see if that helps at all.

 

[dumbo]

Sounds to me like your voltage regulator is bad. The only way you would be getting 18volts out of it is if it was going full field. Take the alternator back and get another one and see if that helps at all.

Yah that sounds about right.

Is the reguator internal in the alternator or external in these cars??

Also just check the voltage at the alterntor with a multimeter..the cigarette light seems like a lot of work for nil..:sarcasm:

EDIT: OHHH!!! and stop driving your car, looks too straight to be burnt on the side of the road.

 

[slightly_red_MA70]

Yah that sounds about right.

Is the reguator internal in the alternator or external in these cars??

Also just check the voltage at the alterntor with a multimeter..the cigarette light seems like a lot of work for nil..:sarcasm:

EDIT: OHHH!!! and stop driving your car, looks too straight to be burnt on the side of the road.

It's internal.
I used an actual charge tester for the alternator for the test, and im not driving it lol

 

[dumbo]

Very good, weird that two would be over charging no? I'm intrigued.

 

[slightly_red_MA70]

PROBLEM SOLVED!!!! Got a new alternator and linkable fuse wire today and all is well :biglaugh::biglaugh:

 

[88_7mge]

hahaha. king of the electrical diagnosis!!!

ok, maybe not, just had the same thing happen on my car. lol, its sad how crappy the quality on those reman alternators can be.

 

[slightly_red_MA70]

I am having more problems now!!!!!!! Another alternator has decided to go on me.... :icon_mad::icon_mad:

I was driving around one day and my battery light turned on and now its undercharging/not charging. When i am around 3000rpm the volts will read 12V but other than that its lower. I have no stereo/amp hooked up or anything. Battery, battery terminals, and cables are all fine. Why is my supra killing alternators?????!!!!!!!

 

[Danlo]

I am having more problems now!!!!!!! Another alternator has decided to go on me.... :icon_mad::icon_mad:

I was driving around one day and my battery light turned on and now its undercharging/not charging. When i am around 3000rpm the volts will read 12V but other than that its lower. I have no stereo/amp hooked up or anything. Battery, battery terminals, and cables are all fine. Why is my supra killing alternators?????!!!!!!!

Do you have the Brake and the Alternator light on when the engine is running?
If so, I had the same problem about a month ago. Atlernator was acting crazy on me. I took it to the store and it was fine. But they gave me a new one still. The new alternator was doing the same thing.
I took the car to the electromechanic and he found the problem right away.

It was the 15A fuse for the ECU-IG at the J/B no 1. The fuse was not bad, but it was not making proper contac. The guy just crimped the legs of the fuse holder and done. I could not believe it.:3d_frown:
This fuse is located inside at the left kick plate. In the first row from the bottom. It is the third from left to right.
I hope this helps.
Danlo

 

[slightly_red_MA70]

Do you have the Brake and the Alternator light on when the engine is running?

The guy just crimped the legs of the fuse holder and done.
Danlo

yeah both of the lights are on. And what did he crimp? im confused on that

 

[Danlo]

yeah both of the lights are on. And what did he crimp? im confused on that

Take like a small flat screwdriver and try to close the gap where the fuse seats.
He crimped the fuse holder it self so the fuse go in tight. Mine was loose and the fuse would not transfer current from one leg to the other. That circuit feeds one leg of the alternator plug. When it is not geting power the alternator starts jumping all over the place.
Let me know
Danlo

 

[slightly_red_MA70]

didnt work. taking my alternator and battery in today to get new ones. hopefully the new ones dont crap out on me within a month too

 

[Danlo]

didnt work. taking my alternator and battery in today to get new ones. hopefully the new ones dont crap out on me within a month too

Sorry to hear that.
That was all I got.:sadwavey:
Keep us posted.

 

[nuggets]

I had a similar problem two months ago. My original alternator crapped itself and didn't charge. I got the brake and battery light on all the time (battery light was dim, for whatever that's worth). I bought a new alternator (rebuilt) and that guy overcharged everything and blew out practically all of my external light bulbs, numerous fuses, the 100 amp fusable link, rear defroster relay, wiper relay, and cracked my battery which then leaked acid all over the place. All while driving down route 80 at night. My buddy in the passenger seat had to light the road with my mag light while I limped home. Yeah, good times. Luckily, I got a new alternator, and replaced everything else and so far all is well. I wish I had an answer to your problem, but I'm not great with electrical issue diagnosis. Definitely keep us posted. After that nightmare I'm all ears when it comes to electrical problems.