914-6 Gen light comes on when hooking up the battery. Options

[Porscheman912]

Ok, I have a friends 914-6 here, and just built the engine in it. Before doing the engine, and after, the Gen light comes on when the car is off. I took the starter, and Alt to a shop to have checked out, and they were both good. Replace the Volt reg with another new one I had, and still on. I have a wiring diagram, but does not show wire colors, or switches. The light would go out in 2nd position on the ignition switch, and then come back on. I dropped the fuse panel down, and now it is on in all positions. It goes out when started. I was getting a very light arc when I hooked the battery up, but when I unplug the alt plug from relay board it goes out. I am thinking it may be the ignition switch itself, and just wondering if anyone has seen this on these cars? It is an OEM 6, not a conversion. Any help would be great, I need to get the owner his car back, and I am still testing things, just trying to save time if someone else has seen this.

[Porscheman912]

Ok, I just wanted to update this since I am finally finished with this car. Ok, the Original Alt was rebuilt 2 times, and gone through a 3rd. I feel bad for the shop that did it, because they have done all of my 356 starters, 911 starters and alts, and my 928 alt. This one was that odd, everything tests good, but dang thing kept kicking the Alt light on. I finally gave up, and ordered a new one. Well, as with the issuse that was going along with the alt, the new one was wrong. I tested it, in the car, and alt light was out. Went to install in fan housing, and bolts were to short. I started looking at it, and it was longer. I went into my loft, and dug around, because I knew I had a few alts that I had not seen in years. Well, sure enough, I had a new one. Tested that, and that fixed the problem.

The owner had told me the interior light would not work with the doors, so before hooking the battery up, I decided to see if I could fix it. Pulled the the switch out of the drivers side wires were there, pulled the one from pass side, and no wires. Reached up around the dash, and no wires. After looking at my 914-6 harness, and the wiring diagram, I found the wire for the pass side, plugged into the gauge lights. It was very melted. Anyways, I fixed that and the other electrical problems. I would almost bet money that the interior light ground wire being shorted, was a big cause of the alt going. I has to have a burnt wire in it. The diodes were replaced twice, and some other parts were, but it still kicks the alt light on. Now that everything is fixed, I wanted to share this with everyone.

No matter if it is new, tests good, and gets rebuilt, sometimes things just don't work. For everyone out there who reads this. I have been working on these cars for years, and it seems that the strangest things happen and they will drive you nuts. Just do your best, and keep checking, sometimes you just need outside advice just to make you realize this stuff does happen.

I just want to thank you all for helping, and I hope this may help someone else.