AC Problems - Help Diagnose

[DonMo]

My AC stopped blowing, I am getting by with 260 AC (role 2 windows down and go 60 mph), but being South Florida and coming in to the months where humidity is higher than temperature (and temps are in the 90's), I want my AC back. Here is what I have done so far:

Removed fan motor from smugglers box, fan works when I apply 12 volts to it. What a mess in there, I cleaned it out and lost the clips, no big deal, I can use wire to hold it closed. The connector tube from the fan housing to the car came apart, I will try to find a replacement.

With car running and ac switch on fan speed 1, 2, or 3, I have no voltage at the connector to the fan motor. I do have power to the relay and fuse in the smuggler's box left side.

With car running, the evaporator seems to be making a noise like a mild hiss (freon moving I would suspect) but not getting cold. I am at an idle with the engine hatch closed but the evaporator fan is out and disconnected.

The AC ran fine up till two days ago, when it stopped all of a sudden. None of the fuses in the trunk are blown.


Any suggestions on what to check?

[fred cook]

Does the A/C system have a pressure switch plumbed into the system? If so, insufficient coolant (and thus pressure) will prevent the clutch from engaging. On the Porsche system, it might also interrupt power to the blower. Also, have you tried replacing or testing the relays to make certain they are working correctly? Last but not least, check all the electrical connections for corrosion or oxidation.

Good Luck!

Fred Cook
'80 911SC coupe

[Zeke]

You can't run the AC system at all if the fan is not working. It will freeze up and turn itself off. (Yes, even a Porsche). The hissing is a good sign. Get the fan going before any further diagnosis.

[DonMo]

Thanks, for the replies. After a little investigation and using the electrical drawings in my Bentley, I found a loose red/white contact on the fan switch in the center console. With a little pressure on the wire/connector, you can hear the compresser engage and disengage, even with the fan all the way out of the smuggler's box. I tie wrapped it into place and it works now. My headache on the connector between the fan and air tube was solved by a trip to Lowe's. There is a 3 inch rubber piece that is used to connect two cast iron sewer pipes that is a perfect fit. The hose clamps worked and all. $4. Sweet. I am cold again. Now to fix the fresh air fan, it is dead (melted pieces).

Any one know how to get the fan off of the post?