Hey, new to posting, but not new to seaching your forums for the odd ball problems, finely broke down and had to post for some help. So my problem is that I can not get my alternator to charge up the battery. Also my charge light and brake light do not come on with the key. Going to sound stupid, but didn't pull positive side of the battery when changing alternator, arched hot lead for a half second then pulled it.

So far I have tested the alternator(3 hours of run time, 14.5-.6v coming from main stud(napa)), removed and cleaned grounds underneath the hood, tried different charge light relay, and tried different volt regulator with no change.
Battery remains charged overnight when it charge it to start.

So what else am I missing or should a say what did I blow up when I arched my hot lead to the alternator? An in line fuse? Another relay(charge lamp is $105???)? Did I blow the bulbs up and it doesn't allow a full circuit(Oil light and dash back like for speedo still work)?

Just got this truck street legal and ready to wheel, so I'm itchy to drive it. thanks any help would be great.

 

Or should a just make a bracket for my 20r and run a Chevy three wire and be done with it?

 

might check to see if it has a charge relay or bad fuse.

 

I have not found a charge relay, on a fuse marked for the alternator circuit. There is no fuse panel underneath the hood on this truck, the wiring has not been hacked into(yet). both of the bulbs for the dash lights are good. Its odd Sometimes I get 0-10v ant at the battery, sometimes I get 12.2, but always 14 out of the alternator.

 

Have you checked that the grounds are clean and making good contact? Any corrosion on the cable ends or inside connections?

 

Yes I have cleaned bolted/ nutted hot/grounds with sand paper till shiny, connections with electronic spray cleaner and a small brass wire brush. I'm really confused to why my lights in my dash don't light up.

 

The arching may have killed the fusible link that is on the + side of the battery, if so equipped.

Are all dash lights out or just certain ones?

Maybe someone more familiar than I with this vintage of rig will chime in soon.

 

yep

http://www.pirate4x4.com/forum/toyot...le-wiring.html

https://www.yotatech.com/forums/f116...toyota-264252/

 

All of my other dash lights light up, Just cant get the brake and charge light to shine. Some people say that the light must be in the circuit for the alternator to function properly, so I'm guessing that would be my problem. I have 14.5v coming out of the alt, 8-11v coming to or from the volt regulator, power going to the charge light relay, but no charge light at the dash. In my wiring diagram it shows a diode in between the charge light and the brake light. Could that have fried?

Does a fusible link contain a fuse or is it just a connection?

I will probably do a couple more tests on my system and if that doesn't work I'm pull everything off and making a bracket and running a chevy. Tell myself that I want to run a winch in the future and not that I gave up 35 year on wiring.

 

Maybe the little bulb is burned out?

 

No they where all good( put it new bulbs it the whole thing anyway.) Well I figured it out, its the fusible link right next to the battery. had 14.5v behind it, but the side that was going to the battery was going from 14.5 to 1.2v depending on what way I moved the wire, but my dash light still don't light up, don't really care unless they matter, volt gauge here I come

 

Hey I'm back with a new problem. So I was out in the woods the other day and noticed that when I hit my brakes my head lights would dim. Truck ran out of juice in the middle of an old back road and left me out at 1AM without sell phone service.

Got it home, the next day I found that my truck was charging at 2v-2.5v. Put a volt regulator I had laying around and kinda scared me. Idle was at 23v-26v 1200-1400rpm was between 50v-65v.....

So I assumed that this other old volt reg was bad, went down and paid way to much money for a new on (5 pin). Still no change 23v-65v. Saw my battery hit 17.5v to make sure I wasn't seeing things and shut it down.

Has anyone ever seen these kind of numbers? Have about ten running hours on new alternator, 15mins on new voltage regulator, checked/ cleand all conections between volt reg/alternator, cleaned grounds.

My charge/brake light does not come on with the key at anytime (before start or running) bulbs have been replaced.

So who has some ideas?

 

You should always replace the voltage regulator when you replace the alternator (assuming you replaced the alternator). And I've always replaced the battery when replacing an alternator too. It is also possible that you got a bad voltage regulator even though it is new and fried your alternator and battery.

 

Brake light works now, not charge light. starting to lean towards the charge light relay is not shooting any power up to the bulb. Is this a load sensing circuit? I have head if the bulb is not in line that it wouldn't charge, but could it be that the volt reg isn't understand what the battery voltage is so it tells the alternator to throw everything it has?

 

So another new alternator and found the wiring problem with the charge light, now idles at 35-45v and I am stumped I didnt even know they could throw that many volts... any one have an idea?

 

https://www.yotatech.com/forums/f120...l#post52199756

For those of you that may have the same problem, I believe that is my problem. 5 pin and 6 pin voltage regulators require a different alternator. I have a none matching set

 

The plug on the alternator is color coded - either grean or black plug. That's one way you can verify that you have the right alternator at least.

 

With the remans you never know, Best difference I could find was around the 3 connector there are letters stamped, top letter for 6 pin is F 5 pin is , unless the internals have been swapped.

 

i put in the chevy 1 wire 100 amp from summit 80 bucks and trail gear bracket - awsome fix

 

did you figure this out? I traced everything in my 1980 and finally got to a solution. If you are still working with this let me know, and I'll try to help. M