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Discussion Starter #1
I've been troubleshooting the A/C on my 2012 Escape for some time now. What seems to be the reoccurring issue is high side pressure builds up and does not allow the compressor to kick on as evidenced by OBD readings. Today it worked perfect but I still fear the high side pressure is too high and the issue will come back.

Low side pressure: 34# by gage
High side pressure: 223# off, 300-360# A/C on by OBD
Ambient Air Temperature: 75F
A/C pressure sensor voltage: 2.28-3.23V

Any R-134 temperature compensation chart will say the high side pressure is too high and when it reaches its limiter will not allow the compressor to run thus no refrigerant cycle. I have confirmed the compressor works based on running it when the pressure is low enough as well as a key on engine off self test of the clutch. Ideas as to what may be causing this? Thanks in advance.
 

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You're right, your high side is way too high. Has the system ever been open or has someone tried to add refrigerant to it? It sounds like either air was introduced into the system or someone tried to put a refrigerant in there that didn't belong. There are other possibilities, but if you know the history, that will take out part of the guess work.
 

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Discussion Starter #3
I believe some was added when it originally stopped working, but I was on deployment and can't confirm this. Best solution I would think is to vent off low side as compressor kicks on and keep cycling until both sides are back in spec?
 

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Nope. In either case, in order to bring your circuit back to spec, a total evacuation, then charged to the proper spec of R134A (I believe you're still 134A)
 
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