2001 9400i A/C problem

This truck came in low on freon. Filled system. Compressor will not come on. There is no power to compressor. Jumped compressor and it will engage. I have power in and out of thermo switch at evaporator. Tapped on pressure switches, unplugged switches and no change. It will eventually engage the clutch for a split second, wait 30 sec. or so and do it will do it again, sometimes. This truck has the a/c module by the coolant tank. I reset it and it will flash red again 3 times.

Any help appreciated.
Randy.

 

I jumped the wire and the compressor engaged. I checked for voltage at the blue wire after the module and there was none. I pulled apart the connector (difficult) and one of the pins was broken. I snipped the wire and made a seperate connector for it. Reset the module, started truck and now the module flashes four times, open to pressure switch. Maybe I'll get some new switches and see what happens.