1985 Toyota 4x4 P/U 22-RE...

How do I troubleshoot why my battery isn't charging...

12.6 volts not running
12.6 volts running

 

Hello...anybody ! ?

Please help

 

Sounds like the alternator isn't alternating. Is that a word?
Anywho, check the voltage out of the alternator on the big wire on the bolt on the side of the alternator. The one fastened on under the heavy rubber cap. If it's good, check to see if it's the same voltage on the battery. If not the same, shut everything down, pull the battery negative terminal off, and check the wire that runs from the alternator to the battery. Again, the heavy wire. If it reads open, there's your problem. That wire is called a fusible link. Essentially, a fuse in a wire.

If the voltage when the engine is running out of the alternator is no good, take the alternator to an auto part's store, and get it tested. If the voltage out of the alternator, and on the battery, are the same, and the wire between the two is good, take the battery in to get it tested. ONE of those three things is bad...

Does that help?
Pat☺

 

I checked the battery voltage with the ignition off and battery showed 12.64 volts...
I then checked the voltage with ignition off at the alternator post where battery positive cable connected [I guess that was it, to much oil on post] and it showed 12.6 volts.

I then turned the ignition to 'on' and rechecked the battery and it showed 12.55 volts and the post on alternator was showing 12.50.

Then I checked the battery with engine running and it showed 12.85 and 13.16 at the alternator.

When you're talking the 'heavy wire running from the alternator to battery are you talking about the battery positive cable.
Or are you talking about the white wire that's going from battery positive to the main fuse under the hood.

Thanks for your reply and help!

Also thank your children for their service and God Bless them.

ANYBODY?

 

The white wire. That's the fusible link.
If the connection on the alternator is dirty/oily etc, that may be your entire problem. Your measure with the engine running is the key.

The battery positive cable runs down to the starter. The heavy cable connection on the side of the starter, under the big, red, rubber cover. The alternator has a fusible link, similar to the one going from the battery positive to the fuse box. That's the one bolted to the side of the alternator under the rubber cap.

I would check all the grounds in the engine compartment too. There should be 4 minimum. 2 off the battery negative terminal, one running to the body sheet metal, usually connected in front of the battery, right behind the headlight bucket, the other, the heavy cable, runs down to the engine block, either connected to the AC compressor mounting bracket, or the engine block where the bracket should mount. There's another ground between the head and the body, running from one of the bolts on the hoisting hook on the drivers side, to the firewayy behind the head. Last is the alternator ground, running from the alternator to the Power steering pump mounting bracket.
Make sure they're all clean, free from oil, dirt, etc, and nice, clean metal where they connect. No corrosion.

Does this help?
Pat☺

 

I previously had the same problem took the truck back to the radio shop and told me all my grounds are clear alternator is fine and i get 12 volts to battery so I went there and it didn’t start he ended up hitting the starter and it turned on so I replaced the starter and now it turns on every start even if I let it sit

 

Thanks for reply...
turned out to simply be a loose alternator belt...