At what point does the compressor cut off on a 1986 420sel? I always assumed it was the ETS that told the compressor to cut off at a certain temperature. In my car I had pulled the ETR out and let the car like that and the A/C would get very cold. I then plugged it back in and with a digital thermometer could only get to about 49 degrees until the compressor cut out. It has been this way since I put it back in. All of a sudden yesterday, on a 93f day, it went all the way down to 44 degrees at the vents and the compressor didnt cut out. Should there be a reasonable explanation for this?

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1984 300SD Orient Red/ Palomino
1989 560SEC
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