What problem are you having???? Quick disconnects are either open or closed, if they are connected and snap into place then they are working properly, if they will not snap together then they are not working properly (could be residual pressure preventing them from connecting), if they are disconnected and leaking then you have a problem and they need to be replaced. if they are connected and leaking then they need to be replaced. There is no such thing as a connect half working unless it is plugged with some crap and it this is true them there is some big problems in the hydraulic system. By plugging in a pressure gauge to see if the qd's are working , this will tell you nothing, the little space between the qd and the gauge will fill a milli second no matter if it's good or almost totally pluged, you will have to install a flow meter to see if the qd is flowing properly. Jim