Need help please, Electrical gremlins Options

[toyota123]

So about a mile away from the house this morning I noticed my windows wouldn't go down, my instrumentppanel wasn't working and also the sunroof was out of commission. The car made the hour drive to work and now it won't start. The wierd part is all of my lights worked just ffine until I pulled into the parking lot at work when they all shut off. I haven't done anything new or changed anythingrrecentlysso I'm kind of at a lossoon this one. Any help you have would be great

[toyota123]

Just got done checking the basics all the fuses and relays appear to be in good working order. Still have 11.7v on battery. Ironically I looked behind my car while in the hatch getting out my volt meter and saw a black hatch across the lot from me. Nextsstep is to try to get a jump, see if I can get it started and test the voltage while running

[toyota123]

11 v while running, turn the lights on and it drops to 9.5 so either alt is bad or something is keeping it from working correctly.

This post has been edited by toyota123: Jun 22, 2015 - 6:53 AM

[Tigawoods]

check the output of the alternator. Volt meter, Pos to the power on the Alt, and ground to the body.

[toyota123]

Was about 10.5 just not sure if it's the root of the problem or a symptom

[Tigawoods]

thats your problem, it should be outputting between 13.8-14.5

replace the alternator

[VavAlephVav]

Yup,
You should be able to stop at an AutoZone or one of those places and have them test the alternator to prove it.
Unless you live in Kalifornistan or something.

[Box]

Definitely the alternator, that or the belt is loose so I'd double check that first just to make sure.

[toyota123]

Well just got done switching the alternator and no luck made it 2 mile down the road and it died again. Truck and trailer in route

[Smaay]

with the engine running, you should get 14.4 to 14.6 volts across the + and - terminals on the battery. if you are not then you have a wiring problem.

turn the key to the on position, check the voltage on pin 2 of the 3 pin connector on the alternator. you should have 12 volts. if you dont, thats your problem. its the voltage needed to excite the stator in the alternator. look for a 10 amp fuse called gauge.

[toyota123]

problem solved it turned out to be a combination of a bad alternator a bad ground wire and ever so slightly loose negative battery cable end all items have been changed and the vehicle appears to be functioning as normal again thank you guys for all the input

[Box]

Glad you got it fixed, sucks you had to pay for a tow though.

[toyota123]

Thought it was fixed. Today it did the same thing so I turned around and parked it. I'm pretty sure there has to be a shortssomewhere, anyone have a good idea of where might be a good place to start

[Box]

I would check all of your body grounds and make sure the contact surfaces are clean and free of corrosion, and that the cables don't have a break in them.

[toyota123]

Thanks box I'll check them after work today

[toyota123]

While investigating I re pulled the electrical socket that plugs into the alternator and the inside of it started to fall apart I think my short might be in that plug because the alternator itself was extremely hot. So off to the junk yard after work to get a new plug.
Will update with results when done

[toyota123]

Well no luck there. At a loss as to where to even start. I unplugged the a/c and some result, pulled every fuse in the the engine bay one at a time still same results. Any ideas?

[Box]

If you haven't checked all of the grounds yet do so, my brother just got a friendly reminder with his '80 T/A on how important grounds are and it doesn't have all of the computers and crap to cause problems.

[toyota123]

Checked the grounds they all look to have good connection the only thing I haven't tried with them is replacing each one. I guess my next step will be to pull fuses and stick a test light in each one to see if I have a short in one of the circuits.

[Box]

Before you start going crazy I'd make sure the short isn't in the battery itself.