Sticking A/C Relay

[TLDG]

I am curious if anyone else has experienced this problem and if any permanent remedy was found:  I have a 2000 ES300 with 143,000 miles, but the problem has existed for several years.  Sometimes, and it appears to be purely random, the relay that controls the electric radiator cooling fans and the A/C compressor magnetic clutch, which is located in the fuse box in the engine compartment by the left fender, sticks and does not allow the cooling fans or A/C clutch to operate.  I have replaced the relay, which costs upwards of $60, more than once, which only seems to be a temporary fix, lasting for 30 days or so.  Now when the relay sticks I open the hood and give the fuse box a firm smack with the palm of my hand (not kidding, LOL), and the cooling fans start immediately and the A/C clutch engages.  I can tell when the relay is stuck because when stopped at a traffic light, the engine temperature will rise and the A/C does not cool the air.  When driving, even at moderate speeds, the emgine temperature remains normal because of natural airflow but the A/C compressor is still inoperative.  Turning the A/C off and back on does not cause the relay to operate, the only solution I have found is the aforementioned "corporal punisment" administered to the fuse box.  A technician at the independant shop that performs repairs and maintenance on my car stated he had seen this same problem once before, but had no solution for it.  I live in Las Vegas, where atmospheric temperature exceed 100 degrees on a regular basis, the problem seems to occur more frequently on hot days, but has occurred in cooler weather as well.  In fact, on warm or hot days when I start my car I open the hood and smack the fuse box before even exiting my driveway on a regular basis just to be sure the fans will be working once the engine has reached operating temperature.  When making multiple short trips running errands to the post office and grocery store, the relay may operate properly or stick on a totally random basis each time I start the engine.   OK, now that some of you (I suspect) have had a chuckle evisioning me slapping the fusebox in the parking lot of the grocery store, do any of you know a real solution to this problem?

[Bykfixer]

https://community.onion.io/topic/784/resolved-relays-sticking/24

Try reading this and see if it helps. About half way down the fun begins but frankly I don't speak "electrician" so I do not understand some of the terms. Anyway it seems the folks there figured out how to resolve the issue. 

[RX400h]

Did you buy your relay from the dealership? It looks like there are multiple cooling fan relays. 

[TLDG]

I have replaced the relay twice, one OEM purchased from a dealership (very expensive) and one purchased from an auto parts store (slighly less expensive).  The problem returns within 30 days or less.  I even removed the cover from the original relay and cleaned the contact points, thinking that perhaps the relay actually operated but carbon build-up on the contact points from arcing prevented the electrical connection.  This also did not cure the problem.  I have isolated the relay at fault to a certainty, so it is not a matter of multiple relays.