What's wrong with the a/c?

I too own a 1996 Explorer. We had a leak from the low pressure side schrader valve. I put a vacuum pump and guages on it and it would hold a vacuum down to around 30 pounds, I thought it was good and recharged it and it lost the refrigerant and stopped cooling. I charged it again and put soapy water on all of the hose connections under the hood and the schrader valves and saw bubbles on the one on the low pressure side.
One trip to Napa and got the valve (around 5 bucks), pulled another vacuum then charged it again. So far so good for over a year.
If she had to add refrigerant earlier this year than that indicates there is a leak, it may not be completely empty but the low pressure switch will keep the compresser clutch from engaging if it is low.
To get the clutch to engage so that you can add refrigerant make a jumper wire and unplug the connector to the low pressure switch from the evaporator canister, jump the two contacts and the clutch will engage and draw in the refrigerant. IF it is a small leak you can nurse it along until it starts losing so much refrigerant that it becomes cheaper to fix it.
I replaced the compressor, evaporator and orifice tube with a kit from Napa for under 400 dollars including the PAG oil and the flush solvent to clean everything out before re-assembly, it was not that hard, studied it on some u-tube videos and tackled it myself.

If you lost Freon then you have a leak. Did you have the leak fixed? It won't work if it's low on Freon.

Her fuse box for the a/c is inside the car. The one under the hood only contains the wot relay but I'll give it a try. Thanks.

Have I got an answer for you.
I have a 95 Explorer and the air conditioner started to operate erractically
and I checked everything. I moved the connector for the diagnostic hook-up and bingo, it started to work. Now, when it quits, I simply raise the hood and tap the ecm connector located on the side of the fuse box in the engine compartment and it works. There is a loose connection inside the connector and I am afraid to try to take it apart. I don't want to make anything else to fail. (wire bundle) If this works, then you can show Ford or your mechanic the solution and let them go from there. The wire that I moved is the end wire going into the connector.