How do I wire up the compressor to force it to run so I can add 134a refrigerant?? On GM's you have to run a hot wire(set) to the compressor but on my old Dodge I remember just running a short wire to bypass a switch as I remember it....but this car is so different. Any help appreciated.

wow, so no one here has had to re charge a Dodge a/c system ? Just to clarify, my compressor won't engage since pressure is too low. therefore I cannot charge it unless I force the compressor to run...just wondering how the easiest way to do this was.

Pull AC clutch relay and jump pin 30 to 87

Jumping the relay will do no good if the system pressure is too low.

There should be a inline pressure switch in the system, it is designed to protect the compressor and shut it down down should the system reach a very low pressure. It should be a 2 wire connection, just follow the A/C lines to locate the switch, pull the connector and jump the wires and the compressor will then kick in.