Another auto air conditioning question

[Midcoastcustoms]

I have a '96 Chrysler LHS and noticed today the air was not working.  So I turned the air on max and opened the hood and noticed the clutch was not engaging and the compressor was not running.  So I put the pressure gauge on the low side and it read 100 psi with the compressor off!  Not good should be 25-45 psi and when it was refilled earlier this year it was around 30 psi.  I have two gauges and both said 100 psi.  Air worked fine up until today and I have not put in any more refrigerant.  Question is this will the pressure go down once the compressor is running or am I looking at other issues here?  I didn't have time today to see if voltage is going to the clutch or do any more investigation.  Any insight would be greatly appreciated.

[cereal killer]

yes the low side pressure will go down once the clutch is engaged.

[Uniac]

Disregard what the gauge says when the compressor isn't running.  I just re-did my Volvo and it read 90 until I turned the AC on.

[Midcoastcustoms]

Thanks guys that's what i figured.  I wanted to run 12v/ground directly to the clutch to see if it would engage but wasn't sure if i was asking for trouble.  Guess now i will study the wiring diagram n see what dictates the compressor turning of or on.  The air worked today but is was real intermittent and not especially cold. 

[cereal killer]

there you go the dealer i work at  sells dodge/gmc/honda mc/ husky chain saws, and i work on them all 

[Midcoastcustoms]

Thanks for the info!  Says relay is in PDC wtf does PDC stand for???  Power distribution center aka fuse box underhood?

[cereal killer]

Thanks for the info!  Says relay is in PDC wtf does PDC stand for???  Power distribution center aka fuse box underhood?

 
yeah pdc=  Power distribution center or under hood fuse block

[Midcoastcustoms]

 
yeah pdc=  Power distribution center or under hood fuse block

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Alright just switched int wiper relay(also has high/low wip relay) with the ac clutch relay.  Seems to work now.  Compressor was kinda noisy so i added a can of oil and refrigerant. This quieted it down a bit.  After adding a can pressure was at 25 psi.  Air is cold enough but could be colder. I could add more refrigerant but my thoughts are this...car had 215k on it so with more r134a wouldn't the compressor work harder thus causing more wear and tear and also would fuel mileage decrease???  Right now with the air on mileage stays about the same.  Was doing all this in the driveway in the dark and lost the low side cap...its always something isn't it?