Hydraulic problem lift mf 194f

Good morning,
I tell you the problem we have with the MF 194F. The tractor while starting the entire hydraulic system perfectly, the Levante axis rises and low without problems. The fact is that if I have the lift axis Arriaba (high arms) and for the tractor it falls, it loses all the pressure and lowers even faster than when it is torn.
I pray if someone has had the same problem can tell me what element is producing this failure, or which one should review again.
First of all, thank you in advance.
Greetings.