Hey Alton,may be the wire on it is short cause your transmission has leaked on it,how I know,I have a 85 nissan 720 4x4,and it happen to me,the green 4x4 emblem on dash worked part time,it's mounted at top of transmission,need a mirror to see,just need to disconnect wire and wipe oil off and wrap with tape real good.Here'a video of my rig.Send me a picture of yours.
Usually the fittings are on the compressor or the lines coming from the condenser. Keep in mind, if the system has not been converted to R134 your recharge hose kit won't fit.
