Fan only works in position 4

Harp · 02-12-2001, 07:40 AM

1988 944 N/A. My fan switch does not work in position 1, 2, or 3. Only position 4 works (works like a hurricane actually). Do I just need to clean contacts? How do I get at the switch insides, etc?
Thanks

todd951 · 02-12-2001, 09:35 AM

The fan speed is controlled by a resistor bank in the switch. It looks like the resistor bank has gone bad, or has a bad common connection. Position 4 bypasses the resistor bank and sends full 12V to the blower, which is why it works in positon 4. I'm not sure if the switch/resistor bank is serviceable, but you can try to open it up and check the resistors and connections.

Harp · 02-12-2001, 11:35 AM

Thanks Todd 951.

But how do I get to the switch/resistor bank i.e. open it up and check the resistors and connections? Do I pull the fan knob off the dash(is there a trick to doing that without breaking stuff?). Any details would be helpful. Thanks.

todd951 · 02-12-2001, 12:33 PM

You'll have to take out the entire heat/AC control unit. I'm not exactly sure how to do that, though.

Harp · 02-12-2001, 12:58 PM

OH. Sounds like more than I'm prepared to try myself. Thanks for the help.

scoober78 · 02-12-2001, 01:52 PM

Had the exact same problem with my 951. I ended up having to replace the entire resistor assembly. I suppose with a little patience I could have repaired it, but a friend of mine actually had one. Can you believe that luck. At the time I called my dealer just to see how much it would have been and the damn thing was like 100$!!!!
Hope it doesn't come to that. I'll see if I can find the part number for you and post it tonight.

Erik

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Go the distance....

Pilot_951S · 02-12-2001, 08:28 PM

The resistor for the fan is located under the black plastic cowling just in front of the windsheild, under the hood. It is not that difficult to get too. There is a tack soldered conact on the resistor that goes bad, using mechanics wire you can repair the resistor by forcing the contacts back together (basically wrap this area and then twist the wire) and place it back into the car.

NOTE: The climate control head in the car is usually not the problem.

[This message has been edited by Pilot_951S (edited 02-12-2001).]

Harp · 02-13-2001, 08:44 AM

Thanks Scoober and Pilot. I'll look at the car tonight to see if I can find the darn thing. I sure would like to be able to fix it myself.

Harp · 02-14-2001, 03:35 AM

I couldn't find it. Maybe I need to "rip up" more of that black plastic cowling that keeps the rain out, but then I still probably wouldn't recognize the thing if I was looking right at it. I know two local really experienced 944 mechanics, but they're $$$$$$$$$$$. Time to crack open the wallet. I tried my Haynes manual but it's only good to '86 and doesn't help a bit.

Pilot_951S · 02-14-2001, 03:05 PM

I haven't done this in a while let me think...

Ok if I remember correctly its on the driver's side, its kind of white ceramic, and its held in by two screws, the part you need to fix you can't see till you pull the unit out.

Crap, I wish I had a pic to show you.

AMCPorsche924Powerhaus! · 02-14-2001, 03:13 PM

Some tuner cleaner might help if you spray it in there...I think it is just actually a rhestat with 4 different positions, I am not sure though.
Sometimes it just gets dirty after years of shooting electricity through there, the greas in it may have got in to the contacts where you don't want it.

scoober78 · 02-14-2001, 05:15 PM

Bad news...

I can't find the part # on my reciept.(my friend owns a part place down here) Anyway the bad news is that he did write down the cost of a replacement from Porsche and it was 135$.

Seems kind of steep so I hope you can fix it or find a better deal somwhere. Maybe someone parting out a car. Sorry I couldn't come through but I haven't bought my parts reference yet.

Erik

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Go the distance....

Harp · 02-26-2001, 07:58 AM

Hey Pilot 951S. Ok, I might have found it. On my 88 N/A it's on the passenger side, but 1/3 the way to the middle. Its kind of white ceramic, about a 1 1/2 inch diameter round disc, maybe an inch thick and has 4 wires going into it. Does that sound like it?

luffa89 · 02-28-2001, 01:21 PM

I had the same happen to me a few years ago, and then after putting it off for about a month, it started to work again and has been fine (knock on wood) for about 3 years. Moral to this story is I think there just may have been some dirt messing up the connection.