TeamSwift

1997 Geo Metro 3Cyl manual.

Problem Description: While driving I push the little square button to turn the A/C on, it lights up AOK and I then turn the Blower Fan of high....works fine for about 5 minutes but then:
1. A/C light (on button) goes off.
2. Simultaneously the Blower Fan goes off
3. Result is no A/C and No fan.

Here's the kicker.....after about 15 minutes the Blower Fan starts to work again EXCEPT for the highest setting. But the A/C light on the A/C button stays off. after an additional 10 minutes or so of driving the A/C will work again (but only for 5 minutes). and then after an additional 10 minutes if I keep everything off....The highest setting on the Blower Fan will miraculously start to work again. Then this whole story will repeat itself over and over again....I can't seem to get more than 5 minutes of A/C

Is this the result of a circuit breaker cooling off and re-setting itself? Or possibly a series of self re-setting circuit breakers? (I tend to doubt this as it's a simple car). Could it be one of those "Modules" in the plastic case next to the battery that's just starting to go bad and/or overheating and then cooling off and working again?

This is a big mystery to me and I would really appreciate a diagnosis and or suggestion.

Thanking everyone in advance for their help, insight, experience and advice.

Phil N Ed didn't go into greater detail, but identified one potential possibility in his posting on Fri Jul 15, 2011 3:30 pm, almost half way down on page 2 of the following thread (my apologies in advance for all the postings you will have to wade through in that thread - stuff that should have been discussed privately between the other members, in my humble opinion) :
viewtopic.php?f=22&t=51324&start=25&hilit=48710

If you have the factory AC (where you adjust the AC compressor belt tension from underneath the compressor), you can see the pictures of the black box he mentioned on my thread, viewtopic.php?f=22&t=48710&hilit=Shoulder#p422612 that I posted on Sun Aug 22, 2010 8:02 pm.

Not having encountered this problem personally, hopefully he or someone else will respond soon. Not the best time of the year to encounter this, that's for sure!
I'm wondering as I write this, if having slightly too little or too much refrigerant in the system could cause your system to behave as you have described. Probably not (I don't think it would cause the light to turn off), but I thought I should mention it on the off-chance it could be an issue.
Good luck and please post if you find and fix the source of the problem!

I believe I may have overcharged the system. The symptom is that the A/C compressor cuts on and off in approximately 5-7 second increments. From what I gather it may be a "over pressure" cut off sensor and switch.

Can someone tell me how I can bleed off a bit of the refrigerant to test this theory?

Thanks in advance.

I'd check with your auto parts stores to see if they have any loaner tools or advice for checking for an over pressure condition, but bleeding off gasses may be against EPA regs (I seem to recall they require recapture and recycling of AC system gasses). That said, as I recall, the charging port has the same type of valve as your tire valves...
Anyway, it's a situation where I'd be concerned about getting frostbite on my fingers and/or accidentally breathing in the refrigerant gasses.