[coleman]

Searched the forum for details on how the climate control works, anyone got any good links?

I just had the A/C recharged and leak tested on my 1993 Fleetwood Brougham. It's good in that respect (whew).

When it was 100°F outside, I'd turn on the car, start the A/C, and my eyes would try to freeze open. After a few minutes, I'd start to notice that the air felt swampy (I live in the DC area) and I when I opened the window the outside air felt frigid

After about 15 minutes, it would suddenly get cold again. Fuses appear to be fine, grounds are fine.

So I'm guessing the A/C is controlled by an upper/lower temp thermistor pair? What else goes into deciding when to turn the A/C compressor on/off. Any way to tell when the A/C compressor is on, since I can't hear it or manually turn it on (that I know of)? Again, fuses and grounds appear to be alright.

I really do appreciate any advice. That and a slightly leaky astroroof are my only complaints. LO5 works great after 205k miles!

 

[caddycruiser]

Not sure as to your specific A/C issue, but mine on the '93 is also weird.

Since it's on Auto, I'm assuming one issue might be that once it gets to the temp. you set, it "kicks off", letting you feel humid/warmth for a bit, then comes back on--right? I've never been able to tell when the compressor was actually on or had shut off for a second, at least while driving with it on Auto.

What do you usually set it to? I stick mine right around 68, then I'll start to freeze sometimes and either bump up to 70 or 72--all on Auto Low. And other times, when it just doesn't feel like working properly that day, regardless of the outside temp., I'll have to put in on 60 and Auto High and it still won't cool very well.

Good to know your '93 is going strong at 205k!! Mine's just barely over 102k, and still, honestly, seems brand new in a few aspects, and my dad's '92 Roadmaster has 191k and seems a little more worn and slower, but still amazing for the mileage and age overall.

Astroroof? I hate you! :worship:...I wish mine had one!

 

[coleman]

One thing I've learned about the astroroof - check the installation! There was rotting cardboard to clean up the sloppy modifications to the headliner board. It was installed as a dealer option by a sunroof company in NJ. Contact cement flowing from the seams, silicone holding the mirrors up... Now I get to rebuild my headliner because they took shortcuts.

Back on topic - I set it at 60°F and it definitely blows at maximum (maximum is something like 45-50°F at the vent if i remember, climate control is supposed to keep it closer to the temp you set). Symptoms are not those of an icing evaportator; which was my first thought but doesn't make too much sense for this case.

It's very very cold as it is supposed to be on maximum, and then it gets warm and humid as if the compressor is cutting off. The evaporator acts as a dehumidifier (all the water dripping from the car) so if it were on I should think I'd at least be getting dry warm air.

I wish I had a wiring diagram for the Fleetwood/Brougham climate control system so I could go chase sensors. Anyone have sensor location data? I have a feeling that there is a cold temp cut off thermistor somewhere that's turning off the compressor, and a turn on thermistor that's not working once the temperature creeps back up. Something to that effect... I do believe that something in the control system is messed up from the age, because the hardware is virtually indestructable.

Any data/schematics out there???

 

[coleman]

Just picked up an original service manual for $17, shipping included... eBay is just awesome. There are plenty of them on there, surprisingly.

That will have the wiring diagrams to chase this down, and get me suited up for the modifications that soon begin.

 

[caddycruiser]

Just picked up an original service manual for $17, shipping included... eBay is just awesome. There are plenty of them on there, surprisingly.

That will have the wiring diagrams to chase this down, and get me suited up for the modifications that soon begin.

I know! I picked one up, in nearly brand new shape, from a guy on there who had a bunch of them, for $10 plus shipping. Not bad at all considering how much stuff is in the thing....like EVERYTHING :yup: