The pressure supplied by the can is what will re-engage the cycling switch. The switch should close at around 45 psi ascending.

Pick up a can of R134a with V dye so you can find the probable leak. Throw a can of that into it and then inspect all the plumbing with a UV light paying particular attention to all the fittings.

Steve

98 Contour SE Sport 2.5 Duratec ATX The wifey's car 89 Taurus SHO - 246K miles 94 SHO ATX - 190K 1997 F-150 5.4L ATX - The Workhorse 150K. ANY THREAD WITH "OMG" or "WTF" ETC IN THE TITLE WILL BE IGNORED!