AC Turns off. Will come back on if manually restart. on 2002 Nissan Maxima

My AC turns off (the RPMs also drop) usually at a stop light. Usually I can press Off and then Auto and it comes back. When it is on, the air is nice and cold. I just replace the cabin air filters since I had not done that for a while. This was happening before I did that though. Thanks

by in Seffner, FL on September 16, 2009
2 answers 3 comments
ANSWER by on October 26, 2009
Hello, Were you able to find out what was causing the problem with the A/C system? Thanks!
COMMENT by on October 26, 2009
Yes, turns out one of my radiator fans was not working. According to the mechanic who diagnosed it, this somehow caused the AC to overload. So, it would shut off. I got three quotes to replace it which ranged from $700 to $280. I went with the $280 at a different shop, Tire Kingdom. Now it stays on. So, I think this was the right fix. I was skeptical. I'm told I need to charge up my AC, but I haven't done that yet. Quote from the dealer was best at $120 for that.
COMMENT by on October 27, 2009
Thanks for the follow up! The radiator fan will indeed cause the pressure in the A/C system to increase to the point to where the system will shut off.
COMMENT by on October 27, 2009
Will this also cause a drop in AC coolant requiring the recharge?
ANSWER by on October 28, 2009
Yes, it's possible. When the fan is not working, the A/C refrigerant (coolant) pressure increases to the point to where the pressure relief valve vents refrigerant to the atmosphere, thus causing the drop that you are experiencing. This doesn't mean that the system doesn't have a leak, which is fairly common under normal operation. I would get it recharged and make sure they add fluorescent dye in wiht the refrigerant, that way if it continues to leak, the shop will have a much easier time finding the source of the leak.