Jinma 454 FEL hydraulics not workimg

[joegis]

It was cold last night—25 degrees and, after starting the tractor, I found no action from my FEL joystick. I could get it to inch up or down if I revved it really high, otherwise it would not move. Last year I replaced all hoses and rebuilt the pump and it worked fine.
Any one have diagnostic help?

[harry]

Does your 3 point hitch operate? Or is this only the FEL.
What oil is in the reservoir? -25 is cold.