OK, well there really is no exact specification for pressures, just so you know. There are trends that relate to heat load, that vary depending on ambient temps, air flow across both heat exchangers, and of course compressor demand (which is variable on these). There are charts we used to use, way back when, but even they were largely a graphic interpretation of generality. That is why I do not think anyone uses them anymore... none of the techs I know do.
This is taken directly from the service manual:
"Pressures And Temperatures In Refrigerant Circuit
CAUTION: When performing work on refrigerant circuit, observe all generally applicable safety precautions and pressure vessel regulations.
The pressures and temperatures in refrigerant circuit are dependent on the current operating conditions (e.g. engine RPM, coolant fan stage 1, 2 or 3, engine temperature, A/C compressor on or off) as well as on the effects of ambient influences (e.g. ambient temperature, humidity, requested cooling output).
In vehicles with A/C Compressor Regulator Valve N280, pressure is modified on the low pressure side by the valve.
For this reason, values indicated in the following table are valid only as reference points. They are attained at an engine speed of 1500 to 2000 RPM and an ambient temperature of 20 degrees C after about 20 minutes .
The connections provided for measuring pressure for the manometer battery are located in the vehicle-specific refrigerant circuit.
At 20 degrees C with the engine not running, the pressure in the refrigerant circuit is 4.7 bar ."
... then the next page:
"NOTE: At absolute pressure, 0 bar corresponds to absolute vacuum. Normal ambient pressure (positive pressure) corresponds to 1 bar absolute pressure. 0 pressure corresponds to an absolute pressure of one bar on most pressure gauges (indicated by -1 bar below 0).
Temperature in degrees C Pressure in bar (positive pressure) of R134a
-45 -0.61
-40 -0.49
-35 -0.34
-30 -0.16
-25 0.06
-20 0.32
-15 0.63
-10 1.00
1.43
0 1.92
5 2.49
10 3.13
15 3.90
20 4.70
25 5.63
30 6.70
35 7.83
40 9.10
45 10.54
50 12.11
55 13.83
60 15.72
65 17.79
70 20.05
75 22.52
80 25.21
85 28.14
90 31.34"
So, again, "in spec" is a WIDELY varied thing.
And like all modern cars, especially those with computer controlled variable clutchless compressors, all the inputs need be correct for proper operation, AND the charge level has to be spot on for best results.