Speedo wiring meltdown

[jeffg59]

I had smoke pour out of my dash due to melting the wires behind my speedo! now the speedo does not work. how difficult is it to change the wiring (easy at the speedo but how about frim there?)? where can i get the complete wiring?
Thanks!

[Walt Fricke]

Jeff

Unfortunately, I don't think it is easy at all to replace wiring, at least not in large amounts. I suggest that you disconnect your battery and pull out most or all of the instruments. Mark/make diagrams of what connects to where. Then hunt through the wiring to find the source of the short, and to determine which wires have had their insulation burned off, and which are OK.

The first thing to do is to fix what caused the problem. Is it a short circuit on a wire which does not have a fuse between it and the battery? There are a few in there. Or something else. Anyway, no good to make the wiring all good only to have a replacement wire start glowing red.

Me, I'd just cut out the old wires and spice in new ones across the damaged parts (assuming no wire is bad for a long distance).

Your speedometer has a ground wire (not too likely to be involved, but maybe), a positive wire (which could be), a sender wire (unlikely, but if its insulation burned off from some other wire, could be the issue), and positive wires for the illumination and warning bulbs.

To really get at things requires going into the trunk and removing at least some of the air circulation plumbing. That is a real pain to do. Then you pad over your gas tank so you can lie in there while working.

The only time I did this was with the gas tank out and hood off after major body work. That really helped, but you wouldn't want to go that far.

I think you can purchase replacement wiring looms, but I am here to tell you that is really a big chore, having done that too. Certainly you could contact one of the Porsche junk yards and pay for a specified section of wiring.

Pelican has wiring diagrams on this site, and those will be your best friends as you trace wires and sort things out.

Let us all know what fried what. Not all that common a thing with stock wiring.