Need help diagnosing AC problem

[luvmy03E53]

Many thanks to all the posters who have come before me! I've learned alot by scanning posts here!

This week my wife noticed that the AC on our '03 3.0i is blowing only ambient air. The blower in the dash is working fine (so not an FSR problem), just not blowing cold air. She took our X5 to an indie shop to have the refrigerant checked, and they told her the car had enough refrigerant and that the pressures were good. In my efforts to diagnose the problem, here's what I've found:

1. Fuses 34, 48, 61 are all good.
2. The aux fan NEVER comes on, not even if the engine is at operating temp.
3. The AC compressor is not coming on and the voltage on the wire to the top of the compressor reads 5.5VDC.

I've read that this could be a defective aux fan, and I'm mentally preparing myself for disassembling the front end of the car, but why is the compressor not getting 12V?

Any and all help with progressing with the diagnosis and repair would be GREATLY appreciated. I'd love to be able to fix this without taking the car to our stealer! Trying to save money on repairs so I can get the 19 inch wheels I'm dying to put on the car!