Euro wiring same as US?

[pete3799]

Trying to fix some electrical problems (fresh air blower and a/c)
I noticed that the bentley shows 21 fuses in the fuse panel for 1978-1980
where as mine only has 18 (79sc euro) the cover shows 21 fuses #20 being the a/c blower. Are Euro and US different?
I have power to the a/c relay in the smuggler box but that's as far as it goes. No
power at the blower switch in the console.
Bentley says with key on i should have power to the blk. wire on the relay. I do not. What fuse should be supplying power to the blk. wire?
I also do not have a blower on the frt. mounted condenser. Bentley shows one but i have nothing there. No signs of there ever being one (no wires up there either)
Is this a problem?

Thanks,
Pete

[javadog]

Most of the wiring is the same. The Bentley isn't always accurate. See if you can get your hands on a Porsche diagram for your year.

Look at your fusebox cover or in your owners manual for the fuse assignments. Euro cars sometimes will not have a front condensor, thus no condensor fan, so maybe a previous owner added one.

JR

[pete3799]

JR
My fuse box cover shows 21 fuses Same as the Bentley.
Maybe I've got the wrong cover.
I'm searching for a diagram.
Thanks.

[white99c2]

I had the exact same problem 3 weeks ago and could not resolve the cause of no power at the fuse terminal. My fuse was 3 up from the top, the top being closest to the windshield. Completely dead and therefore no power at the red wire on the relay in the smugglers box.

I had to run a new fused 25 amp circuit to the relay to make the system work again. Bugs me why it happened and if you do get it figured out please email me so I can try it and eliminate the new circuit I was forced to use.

[pete3799]

azrob226,
I read your thread while I was searching. I think your problem was no power to the relay
where as I have power to it (IIRC red/white wire) but no power to the blk wire.
I'll work on it in the morn. and see if I can figure it out.

[javadog]

Pete,

I ran down to my warehouse and looked at a wiring diagram. It looks like there is a black wire running from fuse 11 to terminal 86 on the A/C relay.

JR

[pete3799]

JR,

Thanks. Haven't been down to the garage yet this morn.I'll take a look when I get there.
My relay had the black wire going to terminal 86,but the Bentley shows it going to terminal
85 so I switched them. Maybe I should switch it back.

[javadog]

Pete,

Porsche has the following wires on the relay:

85 a 0.5 yellow wire to terminal 50, ignition switch
86 a 1.0 black wire to fuse 11
30 a 2.5 red/white wire to fuse 20
87 a 2.5 red wire to terminal C, A/C switch

I don't know what to think about your fuse count, although the fuse blocks were sort of modular and they might have installed only enough for the options on the car. Either that, or a previous owner made some changes. I have a couple Euro cars at my warehouse, a '77 that never had A/C and an '80 that originally did, so if you can't figure it out let me know and I'll run down and take a look at mine.

JR

[javadog]

Pete,

One other thing, before you switch the wiring on the relay. I looked at a later diagram, for '81, and noticed that the arrangement of wires on terminals 85 and 86 is the reverse of what the previous diagram showed. It's possible that Porsche got it wrong on one of the diagrams, although there were a lot of other changes in the A/C wiring of the '81 and later cars. So, before you think about switching the black and yellow wires, go over everything with a multimeter (igintion off, ignition on, etc.) to make sure that you aren't going to fry something.

JR

[javadog]

Pete,

I looked at a third diagram, for cars with A/C and a front condensor and it showed the wiring arrangement for the relay that I first posted above.

Who knows which is correct?

JR

[pete3799]

Thanks JR

Thats a big help .
I'll see if I can trace that blk. wire back to the fuse block.
I only have 3 fuses that get power w/key on and one of them is #11 so maybe
I've got a break in the wire somewhere.

[javadog]

Pete,

Check to see if you have anything on the yellow wire from the ignition switch, with the ignition on.

JR

[pete3799]

Well I've checked the black wire(currently at #86 on relay) and it goes to fuse #13 which gets no power w/key on.
Yellow wire from #85 goes over to the fuse area but it goes to a ground next to the fuse panel (don't think this is right)

So I took the blk wire off the fuse panel and jumpered it (after disconecting the yellow )
Nothing happens at the relay tried touching the yellow to ground still nothing so Iguess the relay is toast.

The yellow wire should go to the starter as per Bentley but it comes out of the harness by the fuse panel. Where should it connect?
I realize that it is suposed to shut power of to the blower when starting but don't know where it goes.

[javadog]

Pete,

Any chance a previous owner has done some re-wiring? If you'll PM me your email address, I'll shoot a photo of the wiring diagram to you.

JR

[pete3799]

JR,

Quite possible on the PO rewiring.
PM sent