Hello once again folks....

The A/C does not function on a 940 I just picked up. I can tell the switch works because ONE time the compressor cycled on and off very shortly, and I began to feel some cold air. I checked the pressure and it reads near 60 psi with the engine off. It is overcharged, right? Does anyone know if there is a high pressure circuit that will not allow an overcharged system to run? Like the low pressure circuit?? Thanks everyone. I appreciate it!! If you have any 850 questions catch me on the 850 board...

It isn't overcharged. Static pressure can be much higher even. The only way to establish pressure is to run the system. If it cycles on and off, even very briefly, it is probably undercharged if anything. if jumping the pressure switch on the accumulator/dryer makes the compressor run (do this only briefly) then you have almost certainly identified a low charge condition, despite the 60psi static pressure.
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chris herbst, near chicago

850 owner,

If you have a pressure gauge.... the pressure in the system (with the A/C on) should range from a low of 25psi, the Pressostat will then engage the compressor clutch until 40psi is reached, at which time the compressor will cycle off until 25 psi is reached again.
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1998 S90 062,925 1995 964 145,750

Chris ---

Sounds like a good idea to me. I'll try that out and see if it works with the circuit tripped. If so I'll just take it in and have it professionally drained and recharged, or perhaps I can top it off myself if it's low.