Calling all Sparky types.....

Hey Frank!

If your car is wired like mine was, the 12v red wire was a daisy chain type set up. One hot that looped from 12v+ to 12v+, gauge to gauge. you should cap off the red wire or clip it at the source.

If it's an amp gauge, the 'S' is for Signal and 'I' is for Ignition (to the 12v terminal on the ignition switch. Don't tie them together. You can cap them off or trace them back and unhook them. 

Ted

I believe you have to tie them together.  AMP meter measures current flow + or -.  Hence the heavy gauge wire.  I'd use a butt connector and securely solder them and protect with shrink tubing and tape.  Those wires are likely not fused and will melt  otherwise.

I don't doubt your experience. Just trying to understand why you'd tie them together? are you saying they lead from the 12v battery to the starter?

Here's more detail AMP wiring:

http://www.classicinstruments....llation%20012313.pdf

Read the page in Wolfgang's link carefully.

If you don't understand what it's saying, STOP and find someone who does to give you a hand. This is potentially very bad juju that could cause a fire or worse. (A heavy gauge, unfused (unprotected) cable connected directly to the battery.) If it accidentally grounds out anywhere, things are going to get very hot in a hurry.

If your car is wired like the diagram in Wolfgang's link (and it sounds like it probably is), you could in theory connect those wires together, insulate the connection very well, and be done.

But it's probably best to disconnect at least one of them at both ends and run a new, shorter, heavy gauge cable from the alternator to the post on the solenoid that's connected directly to the battery.

The thin wires Ted mentions are probably for the lights in his gauges and wouldn't correspond to the two heavy cables you're asking about.

Or that's my semi-educated guess, anyway. It's best not to diagnose this stuff remotely and have someone who knows car electrics have a look.

Thanks Ted, Greg and Mitch.  I was talking about the BIG wires to the AMP gauge. The smaller wires as Ted suggests are great for switched and un-switch power sources. I suspect the same a Ted says with respect to those wires.

I looked at that diagram Greg sent yesterday as I was taking things apart and labelling wires.  And each of the 'S' and 'I' terminals had two wires attached to it.  Not sure but  I'm guessing that they need to be linked together since there are two and they need to be in 'series' for the gauge to read properly.  One of the wires to the 'S' terminal comes from the fuse panel, directly, that I can see. Another I think comes from the Ignition by way of wires coming out of the original column mounted VW ignition and from the firewall by the drivers side. The two wires on the 'I'' terminal were taped with black electrical tape as well as screwed to the terminal. Since the wires are covered its hard to see exactly where they are from but there is a confluence of wires coming out of the ignition.  

I worked with a test light first and found the juice in the big red wires by touching them with the probe and getting a big spark. For sure it was time to disconect the battery. I think I may do a few continuity tests to identify the origin of a couple of those wires.  Alternator and ignition??