Does anyone know how to wire up the voltage regulator so that it will excite the alternator?
I can’t get my electrical system to constantly excite the alternator.

 

You would need to know if it is male or female??

Might just help to know just what your trying to excite?? Year engine those kinds of things

 

I want to signal the regulator to tell my alternator to start pumping out some needed volts. (Or something like that)
Guess the regulator needs some excitement to work. Unfortunately it’s not Self Exciting…. 1987 round plug type nepondenso alternator 22r

 

I want to test the system with a temporary
jumper and then a possible re wire

 

I think the charge light in the dash is the exciter for the alt, if the bulb burns out the alt won't work. You can jump 12v to the 7.5 amp fuse in the fuse box under the hood, this will kick the alt in and it will charge until the engine is turned off. This might not work for you but it is worth a try ,the engine needs to be running when the fuse is jumped.

 

By jump you mean... run a temperary 12v power source directly to the 7.5 fuse circuit? Im a newb to auto electric.

 

You just touch the wire with 12v to the fuse , it is not left on very long.

 

Swampfox said:Unfortunately not a correct statement. Think about it ...it would be a very poor design by Toyota Engineers if your alternator wouldn't charge if the bulb burned out.
In your truck with the key in the on (run) position before you start depending on the options that you may have there are many lights on in your combination meter.
Except for the charge light these lights are all fed from a common buss (printed circuit) in the combination meter, which is fed from the 15a. engine fuse. The charge light is fed from the 7.5a. ignition fuse.
With the exception of the turbo, a/t oil temp, brake and charge all of these lights are on because they are grounded either through their sensors or computers.
When the alternator is not charging there is a path to ground through the yellow wire at the alternator (If your 87 is the same as my 86). The turbo, a/t oil temp, brake and charge lights use this path to ground and that's why they are lit before you start. All of these lights have a diode in the circuit, which prevents them from being back fed once the alternator starts charging.
Your 22r probably only has the charge and brake so let's take a look at these.
The charge light circuit starts at the 7.5a engine fuse, a black/yellow wire runs from the fuse to the charge light printed circuit at the combination meter, through the bulb then the diode to another printed circuit and leaves the combination meter through a yellow/white wire. This wire goes back to the fuse panel and feeds the 7.5a charge fuse, from the fuse panel a yellow wire goes to terminal #2 the alternator plug. This is the "L" terminal of the alternator and when not charging this is a path to ground. The exciter circuit does not depend on the charge bulb to function, it can be excited through the brake bulb as well and this ties into the circuit before the charge fuse, however if the charge fuse was blown, then the exciter circuit would be open.
The brake light indicates loss of brake fluid or that your emergency brake is on, this path to ground through the alternator is why the brake light comes on when you turn on your key and stays on until the engine starts and the alternator starts charging. So if your brake light is functioning properly there is nothing wrong with the exciter circuit to your alternator, the problem is either your alternator isn't charging (generally an open doide) or your regulator is gone.
If your brake light is not coming on when you start, but works when the emergency brake is on then you have an open in the exciter circuit somewhere.
The easiest place to start would be at the charge fuse. Check that it is good, don't just look at it check it for continuity with an ohm meter. I've seen these fuses look okay through the plastic, but be open where you can't see. Next if the fuse is ok, remove it and with the key off check both sites of the socket for 12v to ground. There shouldn't be 12v, but this verifies that fact, next turn on your key check again, if you measure 12v on one side of the fuse, then the circuit wiring and components from the engine fuse to the charge fuse is okay. If everything checks out the next step would be to do a continuity check from the other side of the charge fuse to the alternator plug.

 

Thanks HadMatt

The alternator is actually in an 82 hilux.
Ill try to check these items asap.
it will randomly excite and put out 14volts wile im driving but... not for long. Ill hear the relay come on.
When I test the Alt its puting out just above 12v.

I was wanting to jump a wire from the bat directly to the alt to see if it would excite. I was thinking i could jump the 12volt source to the Sense wire on the round plug.

 

Will the charging system still work even if the radio and Cigarette lighter are disconnected?

 

Padawon Will the charging system still work even if the radio and Cigarette lighter are disconnected?

Shouldn't affect it at all. The battery needs to be charged regardless of the accesories that your truck has.