914-6 Rear Window with Defogger
 

I want to add to my 914-6 (1970) a rear window with defogger.
I do have the rear window and the correct switch.
After a week looking at the manuals and all my related literature, I have not a clear idea "how to wire the defogger"
I found on my Factory Manuals that I need to use a relay on my main board. Unfortunately, I only have two relay positions on my main board and both are on use.
Some one with a clear easy diagram I can use as a guide?
Thanks in advance.
Francisco

Hi,there are 2 boards for the 914/6 as far as I can tell and I believe it was a model year dependant,1 board has the relay pins,you would appear to have the board without this 3rd relay pins,for this application the relay was located in the loom....where I don't know,if its not there maybe this wasn't an option ordered when your car was new.
It really would'nt be to much hassle to wire one in,as far as I can see it maybe your only option.
I have a demist type rear screen and no wiring on it...sucks.
Good luck.

Question: why bother other than to say you have it? Back in the '70's I lived in Kansas City where (at that time, not so much recently) we had a lot of nasty winter weather. I had a '70 914, and later a '70 914-6 (I had the latter for 18 years) for my daily drivers and because of the sheltered and back-slanting configuration of the rear window I can't ever remember needing the rear window defogger option, nor ever having to scrape the rear window. So there a reason that's a rarely-seen option.

Now if you just want it for brag gin' rights, that's another story.

Think the OP wants it working and I guess I want the same for mine?,are you saying they don't work very well or you stuck on" bragging rights" thing:confused:.
Surely the inside must fog up somewhat @ times...just asking ;).
Personally if you have a car you like isn't it nice to have things working ?,cheers.

He is saying you don't need it due to the way the rear window is protected from the elements, both by the sail panels and the rear of the top. I know a guy that will probably know the score

I never had the idea to generate a debate on this forum.
Searching more carefully thru my Service Manuals, I fund a diagram for 1994 model.
My 1970 914-6 have a different relay board, but I feel I can do it.
Nevertheless ideas are welcome.
Keep all of you posted.
Francisco

No, not that way @ all ,not interestested in starting a pissing contest,but was merely asking why it is not required ...Porsche put it there for a reason,they have never been a company to add useless stuff...mostly.
Funny got home today after some recent bad weather and noticed the inside of mine was fogged up....

My last 914-6 (1970) had a defroster rear window and my '71 will when it finally goes back together. I like the look of the defroster window and it was an option, so it will be installed and working. On my '70 I can count the number of times I used it on one hand, nonetheless, I like them.

Cairo, If you have the opportunity to look a the loom, please let me know the color of the cables. Thanks
Francisco