Ford Ranger 2001 Air Conditioning problem

[caymancl]

This morning, after starting the vehicle, there was no power to the air conditioning, electric windows and probably a few other electrical items. I turned the power off and restarted the vehicle to find that only the air conditioning was not coming on. I tested both pressure switches which had close contacts, the fuse # 25, 10 amps is OK. The relais #56A (located in the fuse box under the hood) when pushed manually, will power the clutch solenoid and start the air conditioning compressor. I removed this relais and tested 12 volts on line 1 and 2 that is its coil feed but when the relais is pushed back in place, it does not close and I do not have any more 12 volts feed.

My question is: is there other switches, other than the one on the dashboard and the pressure switches that would control the feed to the relais 56A (compressor clutch relais) in the fuse box?

Thanks
Pierre