Pulling my hair out over a charging issue on a 97 tacoma

How about getting a bat load tester (I got a Hf that is ok) to find put if your bat io ok

 

The alternator plug is suppose to have a switched positive going to it when you turn the key. Its what powers the alternator to run. Its one of the wires that plug in to the alternator.This wire might have a short in it/ the ignition switch might be bad (hit and miss on sending power to the alternator when the key is turned). I think your alternator is fine from what i read on what you have done so far.

 

This feels right. The last few times it’s worked after I’ve fiddled with it it’s worked fine until I turn the vehicle off for a while, and then not worked at all after I start it back up. Feels like a break in the wire that barely touches once in a while. If I were to test those pins for continuity, where does that wire go from the back of the alternator? I tried following it but it disappears into the whole wrapped up wire assembly.

 

Is your Alt-S fuse good, also there is an exciter wire that could fray or break that should be checked.

 

Alt fuse is good. I accidentally destroyed my old one trying to pull it in the autozone parking lot, because apparently some designer thought it was a good idea to put two small bolts through it that you have to disassemble the fuse box case to even see. That was a fun hour let me tell you. Where is the exciter wire at?

 

There are two fuses, alt and Alt-S they're different, Alt-S is a standard ATO size fuse

 

No kidding. Wouldn’t that be amazing if that was my issue. The only alternator fuse I found was the big wisdom tooth one in the engine fuses. I didn’t see any other alt fuses in there. Is the other one under the dash?

 

Nope, under the hood like most of the main running gear.

 

Damn not sure how I missed that one. Looks to be in good shape though. Why can’t it ever just be a fuse?

 

It usully goes to the ignition switch. If I was at work I'd look up the wire diagram for you.

 

You might be able to continuity test it to the fuses.

 

I’m tapping out and handing it over to Bill, the old school 40+ year master mechanic I go to for anything I can’t handle. He’s close to retirement and knows American vehicles mostly, but he really knows his stuff. Hopefully charging systems are similar enough across the board that he can figure it out.

 

Bill said the charging system couldn't be simpler and that all the wire continuity was good and working. Seems to rule out anything except for the new alternator being a dud, going to have him source and install one tomorrow and see if starts/stays working. I probably should just return the alternator and do it myself, but I'm over pissing with it, it's 13 degrees outside, and I don't have a garage. Also I have a nagging suspicion that it's still not the alternator.

 

Try this when you get the truck shut off the next three times. Take off the positive battery cable. Put it on when ready to start the motor. If no light and it starts right up Alt OK, battery OK, something is on or shorted out that is draining that battery when shut off. Radio, turn it off when you get home, see if the battery goes down. Could be a short in the fuel switch that is draining that battery?

 

It was the brand new alternator. It just happened to have the exact same intermittent functionality as my old one. Autozone bench tested it three times (all fails) before they ceded that it was junk, and gave me a new one. Works fine now, if it dies again I've got my receipt and know what to do.

Unless it's possible something is KILLING my alternators..?

 

He had tp have it set on amperge for it to melt.

 

Didn't notice if 1st/2nd/3rd gen but no matter hows the starter ? & don't know if you have an igniter but check connections up to it. I would've thought regulator (internal probably) but you changed alts with same results, any weird aftermarket shit added lately ?...

 

Glad to see you got it fixed.