Will it, or will it not. Illuminating charging question

So, my EJ22 into a beetle chassis swap is coming down the last "5% needed for completion" that is listed in ads for all project and kit cars. You know, "all the hard work is done".

Any way, in my book the hard stuff is just getting going, but I am closing in on it being drivable. So my engine is in, it runs, but I am getting nothing out of the alternator. I have the Subaru charging harness connected to the alternator and the main harness, so at least everything is there on the alt end, on the other end is in question.

After finding this diagram, I am wondering if all it is is a missing warning lamp that is causing the lack of output. What are your thoughts? Can it be that easy? Please say yes.

http://s140.photobucket.com/user/jg_pics/media/Subaru%20Engine/SubaruAlternatorWiring1.gif.html

To answer a few questions that might arise...

The hot from the bugs harness is also connected to the out on the alternator to make sure I have juice in it also.

The Subaru harness is grounded and powered.

Yes I modified (removed stuff) from the Subaru harness, I did start out very carefully, but shifted into 5th when progress was going slower than the speed of my car with the original 1600cc ACVW engine. So there is a possibility something important is missing other than the charge warning light.

I have not had the Alt tested yet, I have been working on the cooling system and exhaust, and I should be circling back to the charging system this weekend, I hope.

Many Thanks, Steve

The short answer is yes. Many alternators will not output if the warning lamp is not connected (i think the 12V to 'activate the field' comes from the warning lamp).

Robbie wrote: The short answer is yes. Many alternators will not output if the warning lamp is not connected (i think the 12V to 'activate the field' comes from the warning lamp).

Well that's good news and what I hoped for.

I will test the Illumination effect this weekend !

Thanks !

You need an alternator lamp anyway. Yes, that's probably the issue.

Now, the really trick way to do it would be to send the signal through a switch that goes open at full throttle. That way, the alternator will stop charging and begin freewheeling. You will gain back the few HP it takes to spin the loaded alternator. Make sure your ignition and computer systems still function 100% at battery voltage and not alternator voltage though.

The alternator light will also come on whenever you are at full throttle just to remind you how awesome you are.

In reply to Robbie:

Love that.

Back before cold air intakes where all the rage, the 80s?, it was alternator under drive pullys. I recall, Hot Rod or another similar mag did an article on how the load on an alternator is based on the electrical load, and spinning it slower did little to reduce the drag on the engine, and a 2 dollar switch saved more power than the 60 dollar under drive pully.

The light fixed it.

Thanks everyone.