Got a 85 yota pickup that has a problem charging. Old battery was bad so i replaced it. New battery was dead by day 2. Got the alternator tested and all tested out fine. All fuses are fine. Nothing seems to be staying on. Could this be something to do with the ignition switch or what?!?!?

Heres how it acted today: had to jump the truck, let it run for 10 to 15 mins, tried it 5 mins after i cut it off and it cranked. 30 mins later it was dead again.

 

Internal or external regulator?

 

Try replacing the brushes in the alternator,sometimes they work fine other times they don't make full contact if they are worn so you may have had a good reading on the beach test but now after driving around they may be at that point where they don't make full contact again causing your lack of starting power again.

If your local parts store don't have them I think you can get them from 4crawler.com for like $9 bucks. I had the same problem and replaced mine and it works great now and it beats buying a new alternator so whats $9 bucks and a half hour max compaired to the price of a new alternator anyway right

Read this
http://www.4x4wire.com/toyota/mainte...nator_brushes/

 

have you tried unhooking the pos. cable to if see it arks? make sure anything that would normanlly cause an draw is off or unhooked.radios,lights,etc. if it does ark you can make a cheap tester by putting a couple of wires with allagator clip on an old 12v buzzer.one pos. an one neg. leave the pos. cable off the battery,hook one lead to the pos. post on the batt. and the other to the clamp on the cable. the short should act as a ground and cause it to buzz. next pull one fuse at a time and listen for a change in the buzzer. that will give you starting place to look for the short. i had car that had a shorted seat belt buzzer and a bad dome light bulb.this how i found them.

 

i'm not sure if the diode pack in the alt could cause a problem ,but you can check it by unhooking all the wires from the alt. take volt /ohm meter set to ohms, check continuity from the pos. stud on the alt to the housing, then reverse the leads and check again.it should have continuity one but not the other.

 

Tried pulling off the pos terminal to look for arc and get none with the ignition off so im assuming nothing is running. Not sure if its internal or external regulated, how to tell? As far as the brushes i may try that. Even if it doesn't work, it can't hurt it.

 

Have a look at this thread.

https://www.yotatech.com/forums/f115...-relay-195034/

 

Thanks aalan and everyone else. After looking at this charging relays, seems like some idiot that owned the truck be4 me decided to take all the relays out except for the flasher relay. Gonna get some more relays in the morning after work and hopefully get this thing back in the woods for hunting season.

 

Your quite welcome. And welcome to Yotatech.