1975 Wiring Harness repair - fix or delete seat sensor wiring Options

[DaveB]

I just removed the wiring harness from my '75. I am not sure what the PO did or what happened but there are a lot of shorts with melted and exposed wiring. The seat wiring is melted into a large uniform mess.

I hate any form of lock out with seat belts. Can I remove the wiring and sensors or is there any reason I should restore the wiring under the seats and then make the modification to delete the lock out and fasten seat belt signals? I can't imagine a future owner thinking they would want to have the wiring available to connect a starter lock out to the seat belts.













Thanks,

DaveB

[StarBear]

YIKES! (IMG:style_emoticons/default/blink.gif)

[windforfun]

Delete the whole harness. Buy a "new" harness. God only knows what else is going on in that thing.

[bbrock]

I love being a contrarian (IMG:style_emoticons/default/happy11.gif) If you have more money than time, buy the RD harness. If you have more time than money, repair what you have. My harness didn't look any better than yours when I started. I couldn't find a good used one and wouldn't have been able to afford the RD harness even if they were available then. I fixed it myself and it looked like new when I was done.

(IMG:http://www.914world.com/bbs2/uploads/post-20845-1535086384_thumb.jpg)

And to answer your question, there are threads on bypassing the lockout. A quick search turned up this one: http://www.914world.com/bbs2/index.php?showtopic=51375

[DaveB]

Delete the whole harness. Buy a "new" harness. God only knows what else is going on in that thing.

I could buy a harness but I'd like to learn how to repair this. I would have liked something that didn't make me say WTF every few minutes.

Oh it gets better.

I need to get a video on how to attach wires like this:



Here is the steering column washer/signal switches with the custom silver Porsche electrical wrap:




and looking down at the bearing for the steering wheel - it looks like the plastic disintegrated and explains why the steering wheel was flopping around.



Probably should have called this Project WTF. I should start a separate thread on the stuff we find in our cars from PO's. Doubt that would survive a few hours on Instagram.

DaveB

[Superhawk996]

Lots of DAPO (IMG:style_emoticons/default/stromberg.gif) going on there.

As Bbrock stated you can salvage it. I you have the money, I'd just find another good used harness and/or start with the new RD 914/6 harness.

New 914/6 from RD gets the nod if only because so many of these cars have old brittle and battle scarred wiring with only slightly less DAPO stuff done to them. Starting fresh would be wonderful.

If you do decide to repair, take a good look at what Tygaboy is doing for wiring as the role model. No matter what you do stay away from hardware store butt splices, low melting temp solder butt splices, electrical tape, and solder.

Proper crimps and tools can be had for less than $100.

[Root_Werks]

I removed pretty much out of my harness that wasn't being used including the seatbelt stuff under the seat. Cleans things up

Oh, what a mess! You have some skills if you can clean all that up! (IMG:style_emoticons/default/blink.gif)

[john ee quest]

I think your PO worked on my 914 cause it looks (the wiring that is) a lot like the wiring in my car. My suggestion would b "delete" not only the seat sensor wiring (which i did many many years ago to my first 914 with no issues). But i would also scrap the whole harness. Which is what i did to my current 914 wiring harness. I bought an aftermarket harness from summit racing. Most teeners will scoff at my suggestion cause I am ruining the "originality" of the vehicle. But iam both an iconoclast and my car is a true outlaw i.e. LS powered, Mendola transaxle, etc.

[JeffBowlsby]

OP has a 1975 914/4 car. A 914/6 chassis harness is not interchangeable with any 914/4. Dash switches/guages relay board connections and more are not compatible. The only 914/4 harness apparently available is from Michael Sanger, but his site is not clear as to which 914/4 model year it is correct for. And I know of no one that has one.

https://www.msbordnetze.de/porsche-914.html

[mepstein]

So many of these cars get parted out. I would look for a new used harness.

[bbrock]

OP has a 1975 914/4 car. A 914/6 chassis harness is not interchangeable with any 914/4. Dash switches/guages relay board connections and more are not compatible. The only 914/4 harness apparently available is from Michael Sanger, but his site is not clear as to which 914/4 model year it is correct for. And I know of no one that has one.

https://www.msbordnetze.de/porsche-914.html

Good catch. I didn't look to see what version RD sells. Just assumed they were makin all flavors by now.

I can say from experience that finding a good used harness for the right model year is like searching for a unicorn. It is a lot easier to say to buy a used one than actually buying one. But I did have luck with people donating chunks of harness to provide patches of color correct wire.

[mepstein]

I have a couple used harnesses but I’m not sure if the later one is a 74 or 75. I’ll be at my daughter’s college graduation for the weekend but can pull it out for pics when I get back.

I found a nos harness for my 71 on German eBay for $850. I got lucky on that one.

[Luke M]

If you have the time redo the harness yourself. I did my brothers 74 2.0 now a 3.0 6 conversion. The main harness remained the same with a few added wires for other gauges to be used. Took me about 4 weeks at about 4 to 5 hours every other day. You can order the correct color wiring so give it a try. I also kept the wiring under the pass seat but jumped out the large yellow wire. IIRC if you cut that out the e brake light will not work properly . Jeff B may know as I asked him when I did it. His advise was to keep it.

Link to my brothers car :

http://www.914world.com/bbs2/index.php?sho...12849&st=80

[peteyd]

We have made several /4 chassis harnesses as well. So they are available from us. They will cost the same as a /6 harness as they are equally labour intensive. Also there would be at least a 2 month wait. We have many orders to fill for wiring currently.

Cheers,
Pete

[barefoot]

Looks like you'd like to understand the harness 7 fix it yourself.
here's the seatbelt interlock fix if you haven't seen this already (the heavy gauge yellow wires). Trace all those other wires back far enough to cut out any shorts.

[friethmiller]

First off, I must say I'm a big fan of Restoration Design's products - especially their in-house metal parts. I actually corresponded with RD on a 914/4 wiring harness during my restoration. They said they'd be happy to do it for me but I'd be charged by the hour with a minimum cost of something like $750. While the cost might work out to something close to the $2500 for the 914/6 harness (maybe more), I didn't feel like I should be the only one paying for their R&D. I simply don't understand why they don't create an early or late style full harness. IMO they'd sell a lot more then the /6s for sure!

I'd recommend cleaning the entire harness and removing any non-original wires or repairs. Next, I'd string it out on a sheet of plywood like the pros do it - using nails to hold it down. Take it one section at a time and simply make repairs and/or replace entire runs of wire at a time. Make sure you use the same gauge/color wire when possible.

[JeffBowlsby]

There is no 'early' or 'late' chassis harness. There are at least 7 different 914/4 chassis harnesses and they are not interchangeable.

https://bowlsby.net/914/WiringHarnesses/doc...nessIDGuide.pdf

[FlacaProductions]

RD will sell you the wiring in factory colors/sizes - just email or call them. They're very helpful.

[914e]

RD will sell you the wiring in factory colors/sizes - just email or call them. They're very helpful.

That is great for some of my damaged or missing wires and bought the closest I could find and hand painted the stripes on them.

[DaveB]

I appreciate all the input and suggestions.

I don't need a new complete harness. I'm adding a different ECU, so I have the engine area covered. Sounds like I can delete the seat wiring. So my focus is understanding what I have in the cockpit wiring and rebuilding it. Even though I've got a lot of issues with the wiring, it is complete. I have some time before I can start welding on the car, so I don't mind figuring out and repairing this harness. We've all been there before - we get a great deal on a car and then spend 5x more what a good driver would cost fixing it ourselves.

BTW - RD produces the best sheetmetal I've received plus great service.

Now I just need to mark where everything goes.





DaveB