A/C Condenser Fan inop

[Skrapbob]

1992 automatic.
My A/C is great if i'm rolling down the road, but stopped at a traffic light, or anytime at idle, the system stops blowing cold air. The condenser fan is not powering on. I installed a new condenser fan because I thought the old fan was faulty (there is power at 1 of the 2 wires going to the fan, should they both have power)?

The Ford manual states there is a 15a fuse close to the fan but I can't locate it. Maybe the fuse is only on factory air cars. I don't know if my car is dealer installed or factory installed. There is also a dedicated condenser fan relay only on cars with automatic transmissions located forward of the battery.

Any ideas? Any advise in appreciated.

[bravekozak]

The 15A inline fuse supplies power to the condenser fan motor on the yellow wire.

Also check your refrigerant pressure. Low pressure means no activation for the compressor fan relay.

[sc72]

Scrapbob, the AC unit in our 92 GL has never been efficient at rpm's less than 2000 anything above that number and the AC works fine. Good luck and if you find a way to help it cool at a idle let us know.

[Skrapbob]

Thanks for the replies, it gives me motivation and helps the search. Weird, it does seem to be the rpm's. I have noticed it stops cooling if I coast to a stop. I will look again for the inline fuse. I would still like to get the fan working.

[bravekozak]

Just follow the yellow (brick) wire.

Check out what I bought yesterday on the bay!
I will just go to a garage with a vacuum pump.
I saw a YouTube video and A/C is very easy to do with a completely empty system.

[Skrapbob]

Wow! You scored Brave! Good luck with it!

[TorqueEffect]

Yeah I am just going to use Envirosafe R12 R134a replacement, basically it is just propane and you don't need to flush the system, or put a vacuum on the system when charging it for this stuff.

What type of oil does our compressors need? I am skeptical of using their brand oil charge, because I don't know if it will mix well with the residual R12 left in my system.

[Skrapbob]

Okay, the yellow wire is hot (I still can't find the inline fuse). I only used a test light to check it, but it is hot even with the ignition off. I am not sure what the other (green/red) wire is for.

Two years ago the shop checked and charged the system and installed one can of R12

I just did a thermometer check at the main vents in the center of the dash. I used a fluke digital thermometer.
Car is parked in the shade.
The outside temperature: 98 degrees.
Dash vent at idle: 75 degrees.
Dash vent at 2000 rpm while parked: 57 degrees.

You guys really know these cars!! Is a working condenser fan even going to help? There has to be a reason they were installed on the automatic transmission Festivas.

[navdoc101]

They help at idle.

[bravekozak]

Yellow should be hot at all times. Forget about looking for the inline fuse.
Green/red goes to the condenser fan relay on it's way to ground. I believe the condenser fan relay is A/C relay #3. The condenser fan relay solenoid is energized through the refrigerant pressure switch. Do you have power going through the refrigerant pressure switch? If not, pull off the boot and jump it for a couple of seconds to see if your condenser fan comes on. If it does, then you either have low refrigerant pressure or your pressure switch is bad.

[Skrapbob]

Good information bravekozak. I can feel the relay click when the A/C switch is engaged, so I think the relay is okay. Next I will try the pressure switch... when I get some free time. :-)

[bravekozak]

Skrap, is it very hot in Kansas? I am wondering why I am bothering with the A/C after last winter. The Lakes are so cold, the last three nights, the temp was 12°C (57°F). It's only 22°C (71°F) during the day. It's about 5°C below normal. I know the Indy guys will enjoy the cold air down by the lakeshore.

Is your pressure switch working? I hope so. They price gouge on those switches (because they can).