NEW BATTERY AND ALTERNATOR STILL NOT CHARGING HELP!

Looks like he is close to @j4roe
Maybe those to can get together and figure it out.

 

^^^^This right here needs to be tattooed on the TW forum's forehead.

 

Sorry I’ve been inactive I just got back from work and have been trying all the ideas y’all have given me, so far nothing has worked. if you would be willing to lend a hand I would love to have your help and a 2nd pair of eyes on the truck.

 

Have you ruled out a loose ground wire? I'm not sure how many there are to check but there at least two I think. Engine grounds I mean. One is in the back near the firewall I believe.

 

I have, I’m pretty sure it’s a alternator wire, I made another thread on trying to find it

 

I am pretty sure you guys are right on with the 3 pin wire that goes to the fuse box the charge light in the cab does not light up with the key on even with a new bulb and that is triggered by that same 3 pin plug. OP wasn't able to get the plug off the fuse box and said it was stuck so he couldn't test for continuity. I am going to see if I can find somewhere to buy pig tails of both ends and I will make a new wire he can just remove the old plug (even if it breaks) and install the new one. Or if he can get the original off intact and clean and repair it to be usable that is also a option.

 

Did you check the ALT fuse (or ALT-S)?

The 3 wires are real simple. Check that one has 12 volts all the time. One probe on the end of the connector, other probe on battery negative.

Check that one wire has 12 volts only when key is turned to ON.

The other wire is usually yellow. That one goes to the warning bulb.

And are you sure the connector is seated completely? Sometimes it's hard to push all the way on if it's rubbing the opening of the back of the alternator.

 

I did, me and @Hamburgler_101 we are trying to work on it. At the moment we are pretty sure it’s the connector that should be replaced since there is a bunch of crap in it (the alternator plug) and we might have to rewire it all.

 

Check the ALT 120A (yellow) fuse in the main fuse box under the hood.

 

testing for continuity is fine... you need to be checking if the wires can pass amperage and that can only be done with the circuit loaded and by performing a voltage drop test.

 

Oh my Christ, is this fixed or what?!?! It’s not the space shuttle. Probably not worth fixing, I will give you a grand for it.

 

The biggest clues here are in post #1 and #4.

The alternator is GOOD - Post #1
The alternator Output is the same as battery voltage @ the terminal on the Alternator. Even when the truck is running, and at any RPM.

Alternator is not always charging, it has to be told WHEN to charge.
And at what rate to charge.

OP, has been offered help by @j4roe
Between the 2 of them, they should be able to solve this.

Good luck guys.

 

So I did everything you said none of the plugs responded at all and I tested them all for about 10-15 seconds each, thought it was my multimeter but I touched the ends together and they showed up. Is there any other possibilities?

 

Even though the auto parts store said your alternator tested fine, I'm not so sure I would trust that. Take your alternator off and check the condition of your brushes. Worn brushes is a common reason for alternator charging failure.

https://www.youtube.com/embed/71_kBhg6_-A

 

Hey guys,

This is random and my knowledge is limited. I had an issue two years ago with an '01 where the battery would charge intermittently. Turns out the harmonic balancer was shot, sometimes sticking and charging and sometimes loose/slipping and draining the battery.

The check is easy by loosening the belt tensioner for the alt, slipping the belt off and then trying to move the pully (harmonic balancer) on the crank shaft. These other folks know more than I do but it's an easy diagnostic that may help.

https://www.tacomaworld.com/threads/recharging-system-issue.555600/​

 

That was a wild ride you went through on that harmonic balancer issue man. Nice to see you shared and documented here on forum to help folks in the future. There is bound to be more that end up with a similar/same scenario someday

 

I’ve installed a new 3 pin connector to the alternator and my battery light still doesn’t turn on and the alternator still isn’t charging. I’ve tried almost all recommendations so far. And to update you the alternator passed all the test and it’s also a new battery in as well. Any ideas?

 

Are you getting the proper voltage at each of the pins on that connector when the key is off and when on?

 

A 2000 Tacoma still has a voltage regulator. If the alternator is good and it isn't charging the battery that is the first thing I would look at.