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Sat Oct 31, 2009 10:47 am

What is this box that the red arrow is pointing to and is it important?

Sat Oct 31, 2009 10:53 am

nolyg wrote: What is this box that the red arrow is pointing to and is it important?]
I think it's the relay that runs the rear window electric defog/defrost.

it's only important if you want it to work. The switch that controls the relay is usually out of sight under the dash. it's a very low-profile rocker switch.

The lore is that the element in the rear window tends to fail, so even if the relay is working and it's hooked up correctly, the defrost may not work. Keep in mind it's probably a very heavy current load, so you don't want to run it much without the engine running (and charging the battery).

Sat Oct 31, 2009 10:57 am

gevmage wrote: nolyg wrote: What is this box that the red arrow is pointing to and is it important?]
I think it's the relay that runs the rear window electric defog/defrost.
You are correct.

Sat Oct 31, 2009 10:59 am

I've disconnect all the wires from the box and put them together. About a month ago one of the wires (fused) was burnt. I've been having charging issues every since then.

Sat Oct 31, 2009 3:46 pm

You were saying you had a problem keeping the battery charged earlier and your alt. light stayed on. Is the wire from your alternator TO the battery (B+ on alt.)correctly installed? I had the same problem on my '74 SB, turned out the wire was shot, swapped it out and never had a problem again!

Sat Oct 31, 2009 3:49 pm

nolyg wrote: I've disconnect all the wires from the box and put them together.
Why would you do that?

You just created a dead short.... lucky the fuse went and not your entire harness.

Sat Oct 31, 2009 3:49 pm

what does that wire connect to?

Sat Oct 31, 2009 3:54 pm

Glen,
I didn't put the wires together until I had problems with the one wire. I changed the fuse first, I was still having the charging problem so I disconnected the wires for the box and taped them all together. I continue to have the charging problem.

Sat Oct 31, 2009 10:32 pm

That fused wire goes to the regulator which is wired to both the battery and the alt/generator - the areas where you're having problems. The wiring diagram has it all laid out for you.

Sun Nov 01, 2009 6:10 am

my regulator is built into my alternator.

Sun Nov 01, 2009 8:03 am

nolyg wrote: I've disconnect all the wires from the box and put them together. About a month ago one of the wires (fused) was burnt. I've been having charging issues every since then.

Are you saying that you took four wires from your car, disconnected them from the "box" (relay), and taped them together TOUCHING EACH OTHER? I may have mistaken what you meant, but if you did that, that's possibly the stupidest thing I've ever heard. [later edit: I apologise for the tone. However, the sense still stands--it sounds like you're possiblly doing some potentially very dangerous things with your wiring. Your alternator problems may be a result of a careless "taped them together" that you did without thinking about the consequences.]

You're also the guy on the other thread who's having problems with an alternator light and can't seem to get it connected right?

Now, what possibly saved you from shorting out your entire wiring harness and possibly burning the entire car to the ground is that BOTH power wires to that relay are fused.

Let's take a step back. Searching back through your posts, you installed an alternator in your 71 Super two years ago, I believe. However, relatively recently, you've been doing very questionable things with the wiring under the back seat, and your alternator has stopped working properly, and you're having these problems with the the wires that used to go to the relay.

Why don't you go through and check the following things to make sure that nothing really bad is going on:

One wire to that relay is brown, it is a ground wire. It can safely be left disconnected on the bottom of the compartment. If I have your year correct and the diagram correct, there are also two white wires and one black wire that go the relay. Tape each connecter up SEPARATELY so that they won't ground out against each other or the body of the car. Remember that electrical tape is NOT a permanant connection. So maybe put electrical tape around each connector and then maybe duct tape around that. That sorts out the relay wiring.

NOW. You're having charging problems with your alternator. Your charging problems are consistent with the idiot light wire grounding out somewhere. That is, the light comes on with the key but doesn't go off with the engine running and the alternator appears not to charge.

Why don't you now go through and check the wiring for the idiot light and the alternator. You had to change all that wiring when you installed the alternator, possibly something's become disconnected.

Two important connections. There's a fat red wire from the big screw terminal on the alternator that ends up at the back seat and used to connect to regulator terminal D+. There's the fat red wire that goes across the back seat that used to go to the B+ terminal of the regulator, and this is perhaps spliced to the fat red wire that goes through the harness to the front of the car. The D+ wire, the B+ wire, and the wire to the front of the car should be connected together SOLIDLY (not just taped) and protected VERY CAREFULLY so that they don't ever touch the body or any other wires, and of course DISCONNECTED from the generator regulator.

The other connection is the generator "idiot light" connection. This light is easiest to put right where the generator light goes, because it's already wired correct. The barrel of the light is hot when the key is on; your oil light works (I assume) so that part is probably wired correctly. The center terminal of the generator light will have a wire plugged into it; if you re-used the generator light, that wire will be colored blue, I believe. That wire needs to end up attaching to the small terminal on the alternator, which is the other one that's not the Battery wire nor a ground wire. If you re-used the generator wiring, I think the normal way to do this is to splice the blue wire from the idiot light to the green "field" wire that used to go to the generator's DF terminal. Those wires are spliced under the back seat. Both wires should be DISCONNECTED from the generator regulator, attached together, and then carefully INSULATED so that they don't touch the regulator, the body of the car, or any other wires. Then the end of the green DF wire in the engine compartment plugs into the idiot wire connection on the alternator.

My suggestion is to check all those connections then get back to us.

Sun Nov 01, 2009 8:26 am

gevmage wrote: nolyg wrote: I've disconnect all the wires from the box and put them together. About a month ago one of the wires (fused) was burnt. I've been having charging issues every since then.

Are you saying that you took four wires from your car, disconnected them from the "box" (relay), and taped them together TOUCHING EACH OTHER? I may have mistaken what you meant, but if you did that, that's possibly the stupidest thing I've ever heard.
I'm pretty sure the wires he wrapped together are the ones coming from the disconnected relay, not from the cars wiring harness.

Max

Sun Nov 01, 2009 8:33 am

Max Welton wrote:
I'm pretty sure the wires he wrapped together are the ones coming from the disconnected relay, not from the cars wiring harness.

Max

I agree. And fortunately for his car, unlike a lot of the Beetle's wiring, BOTH hot wires going to that relay are fused.

HOWEVER, if I discover that someone who randomly tapes wires together in a car KNOWN for having lots of UNFUSED wires coming straight from the battery, somehow his alternator problems become much less mysterious. Sorry to hijack this thread, but one begins to suspect that the alternator/alternator light wiring that he did has something sketchy that's begun to short out and is causing the other problems.

[EDIT: Oh, I see what you mean, that perhaps he disconnected the wires at the supply end and taped them together. Could be. However, his original statement says "disconnected from the BOX" so it may be the other ends were connected to the harness still.]

Sun Nov 01, 2009 9:10 am

A nice close picture of what is connected to what would be nice. Might eliminate these internet communication problems. If nolyg is still reading this, that is.

Max

Sun Nov 01, 2009 11:25 am

Max Welton wrote: A nice close picture of what is connected to what would be nice. Might eliminate these internet communication problems. If nolyg is still reading this, that is.

Max

Yah. A pic of the wires going to the alternator, and the wires around the old generator regulator.

Sun Nov 01, 2009 12:12 pm

yes I am. I'll get those pictures uploaded today.

Sun Nov 01, 2009 2:01 pm

here are some pictures. I don't think my previous wiring was bad, as I got the instructions from here. In the 3rd pic the wires in the tape were all connected to the regulator before I install an alt.

Sun Nov 01, 2009 4:19 pm

Hey thanks for the photos.

nolyg wrote: here are some pictures. I don't think my previous wiring was bad, as I got the instructions from here.

Well, that matches what you've said. If it worked for over a year, then the initial wiring was presumably correct, or at least equivalent.

Quote:
In the 3rd pic the wires in the tape were all connected to the regulator before I install an alt.

Right. It looks like those four wires coming together is the main voltage line. One wire from the battery, one from the generator, and one to the front of the car (and then one to the defroster relay).

Is that held together by anything but black tape? If that's all it is, you should really get a better way to tie those wires together. That point carries the main electrical load, which can be 30 amps or more for short periods. It's really important that that connection is very good, a weak connection can get hot and arc. The best thing to use is an electrician's split-bolt connection or something like that. You could use a cable tie if you're desparate.

That's the first thing I'd check.

It looks like you have all three wires hooked up correctly to the alternator. One thing--the main battery lug looks like it has a LOT of rust on it. You might want to clean off at least the nut on that connection so that it gets good contact, since again, that carries 20 amps plus when you have lights and stuff on.

And it looks like you have the brown ground wire hooked to the alternator, which is good. Where does the other end connect to, the one that was originally connected to the regulator body? It should definitely be grounded to the body.

Speaking of grounds...did you paint the alternator when you put it in? The ones that I've seen, the regulator is colored black, but yours is silver like the rest of the body of the alternator. Is it painted where it rests against the pedestal? If it is, you might have a problem with the alternator getting to ground.

Oh, and just for sanity's sake: it looks like you spliced the blue wire from the front of the car to the green wire to the back of the car. I assume you've checked that splice to make sure it's still solid, and it doesn't pull apart if you pull on it gently. Sometimes splices will fail and make intermittent contact .