Mystery wire from 964 fuse box

iamtheari · 08-22-2011, 08:53 AM

In my 1990 Carrera 4, there is a pair of red wires going from blades plugged into a fuse holder in the front-boot fuse box and leading down and into the area in front of the environmental control system (or at least that's my understanding of where they are leading). I can't see without spending some time pulling pieces of the car out where they actually lead. I should have written down which fuse holder (number and name) they were plugged into but I believe it was #34 and fuel pump related.

What I am wondering is this: Is this a common hack/fix/modification on these cars? If so, what is it? If not, then what would you recommend for me to do in order to ascertain the purpose and function of this pair of wires? Thanks.

Chakka71 · 08-22-2011, 02:18 PM

Could have been a kill switch that was mounted in the car for security? Mine actually had the same
thing from the PO. When I wired in my kill switch to for racing using the fuel pump as my shut-off there was a blade with a wire wedged into where the fuel pump fuse plugged in. I had remembered reading thru the PO's notes that he had a kill switch in the car(it was really a jerry rigged job). Followed the wire and traced to under the dash hooked to nothing.

When I took it out, due to the blades expanding the receiver end where the fuse plugged in it made the fuse loose. Driving down a bumpy road one day I lost power! Thought about checking the fuse since that was the last thing I had worked on and sure enough the fuse was loose. Bent the contacts in opposite directions for a snug fit and it started right back up.

May not be the issue, but sounds awful similar. A picture might help.....

iamtheari · 08-22-2011, 04:26 PM

I think you nailed it. I went out to take pictures for you and tried to trace it a bit more than I had before. I couldn't see for sure where it went but it appeared to head toward the firewall (is it still called a firewall when there is no engine in front of it?) as it ducked under the climate control gadgetry. So I peeked under the glovebox and sure enough I had two red wires coming into the interior compartment, leading to a small on/off toggle switch under the glove box with an inline fuse. Thanks for the hot tip, I'm 99% sure you hit the nail on the head.

And my car to-do list just got one more item: remove stupid switch and ensure fuel pump fuse is seated properly. I like those $0-expense items.