1980SC

Okay, my heater fan in the engine bay works. Tested it with 12volts. Problem is, I can't activate it from inside the car.

I have a 1980SC with the 10 position dial and one lever between the seats. After reading through my Bently manual, I'm thinking a previous owner may have added the the manual heat lever themselves. It opens and closes the heater boxes underneath the car. None of the Bently manual photos show a car with both the 10 position dial and a heater lever. Did any?

The automatic heat control is a lost cause. The circuit board is missing that is supposed to be under the dial.

I just want to find the lousy wire between the seats that powers the fan. Where is it? What color is it? I've been through all the fuses and the relay. They're all fine. Anyone know how I can get power to the fan?

-Rob

Sean Hamilton

G'day Rob,
I'm new to Porsche but I too own a 1980 SC and it has the auto heater control and the single eject lever. I'm informed by my mechanic to "never touch it!" It's only purpose I can gather is for manually operating the heater when (not if) the circuit board dies. Mine did die before I purchased the car and so I used the manual lever for heat. Only trouble was it wouldn't stay up - I had to put my cigarette pack under it to keep it up for heat. I've since had the circuit board repaired, wasn't too expensive and the auto heater works like a charm now.

As a bonus I've discovered this little gismo is great for shutting the kids up.

They've curiously enquired (read pestered me) about the little red lever between the seats, smacking their paw as they attempted to yank at it.
Naturally I replied that on this forum they call it the ejection lever, just like a fighter pilot has and that's also why we've got a detachable roof! They're thinking "yeah okay, that makes sense, so ....must be fairdinkum"
Now, worried silence, when they hear the little servo motor whirring away whilst observing the eject lever rising all by itself! waiting .......waiting ........., Cruel aren't I.

Cheers,
Sean.
1980 Hellblaumetallic SC Targa.

1980SC

Thanks for the info Sean. It's nice to know that my setup is original. I didn't realize that the automatic heat system actually raised and lowered the "eject handle."

Could you explain when the blower in the engine bay comes on? Always on? Just when the lever is all the way up? Does it have different speeds? I assume you can hear it running. Mine was pretty loud when I hooked a battery up to it.

I myself have been waiting for a passenger to ask what the red lever is for...

Thanks,
Rob

Sean Hamilton

Gee,...... I dunno Rob, I'm stumped on that.
Did you read (laugh at) the Chris Blum post - "Who designed 911 climate controls?" You'll be in fits but maybe there is a clue in there somewhere?
No, I can't hear any fan above engine idle let alone driving, but then again I'm not hunting for it either.
The only fan I can ever hear is the A/C and the dash top vents fan.
All I know is that the red lever goes up and down all by itself according to the temp/dial setting and the thermostat gismo above the rear view mirror. An early attempt at auto climate control?

Sorry I could be much more help Rob.
Maybe Eric '86 Targa @ http://www.bradway.net/porsche could chime in here?
Eric wrote: "BUT! You have to use the red ejection levers to open the valves from the engine to provide heat. Since you are lucky enough to have a Carrera, you also have a **** on top that controls the fan speeds in the kick-panels so the heat actually makes it into the cabin. The heater, when set on full blast and footwell blowing literally cooks my toes when I wear Birkenstocks. The neat thing is you can feel the engine temp increase as you accelerate without looking at the gauges"

Cheers,
Sean.

Cheers,
Sean.
1980 Hellblaumetallic SC Targa.

1980SC

You've been more of a help then you might think Sean. Thank you for your comments. I now have a better understanding of how the automatic heat is supposed to work. Perhaps someone else may know how the heater fan is triggered?

-Rob

saint

Hi Rob, I thought that fan was triggered when the automatic heat control went onto thew max setting, labelled "def". I am not sure if it was triggered by a micro switch on the ejection lever at the top of the travel or whether it was an output function of the electronic board.

Bottom line is, I have only ever heard it when the system was set to maximum. It triggers a relay in the engine compartment on the electric board. May be a yellow wire with a red trace, but I am very rusty on the memory of that one.

Good luck
Saint

1980SC

Thanks for the info. I think I may wind up pulling the fan, and converting to the pre-'75 heat setup. Cleans up the engine bay nicely, and no more of this eletrical crap.

-Thanks,
Rob