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As part of a wider renovation, I have proactively replaced my functioning AC compressor, pressure sensor, drier, and orifice tube. The AC functioned properly prior to my disassembly. Therefore, I have no justification to believe that the first compressor malfunctioned and obstructed any pipelines. I have used a recently acquired Denso compressor and a Hella pressure sensor, both of which had the accurate and appropriate component numbers. I evacuated and replenished the compressor with the accurately determined quantity of PAG oil.

Currently, I am facing an issue where the system is unable to accept any refrigerant. More precisely, the indicator light for the AC button does not remain on when I attempt to charge it. I believe that the lack of engagement or compression of the AC compressor is the issue.

This is my attempt:

Evacuate the air conditioning circuit for a duration of 90 minutes in order to eliminate any moisture, and maintain the hoover for a period of 24 hours to confirm the absence of any leaks.
Attach the AC manifold to the appropriate valves, ensuring that the R134a in a self-sealing can is connected to the relevant valve.
The engine is now operating with the fan at maximum speed and the cooling system set to its highest level. When the AC button is pressed, the light promptly turns off.
Evacuate the refrigerant pipe of the purge manifold to eliminate any air present in the hose.
Attempt to inject refrigerant only into the low pressure valve. Do not tilt or jiggle the can while it is being charged.
The pressure on the low-pressure side manifold gauge gradually increases from a vacuum level to around 75 PSI and remains constant thereafter.
The pressure reading on the high pressure side manifold gauge remains at 0 during the whole duration.
The R134a canister remains at a constant temperature and weight, suggesting a lack of refrigerant circulation inside the circuit of my automobile. I have allowed it to remain undisturbed for some minutes without any alteration.
I have also attempted to use my first pressure sensor. No modification.

In my understanding, the immediate deactivation of the AC button light upon pressing it indicates that the AC compressor is not in operation. I believe it is the obstacle blocking the system from charging. I expected the compressor to begin its operation once the pressure sensor determined that there was a sufficient amount of refrigerant in the system to enable its functioning. Nevertheless, that is not occurring. This situation seems to be a classic example of a chicken and egg dilemma. These are some statistics obtained from VCDS when the engine is running and the refrigerant is attempting to charge, but is now stuck at a pressure of 75 PSI.

Programming instructions:

The address is 08 and the component is Auto HVAC with part number 420 820 043 G.
The A/C Regulating Valve (N280) has a current of 0.030 A.
The A/C Regulating Valve (N280) has a failure rate of 0.0%.
0.4 bar Measurement of the pressure of the refrigerant, specifically referred to as G395.
The current shut-off condition is 3.0.
0.0 Current Reduction Request
162.0 Compression Shut-Off Request
The temperature is 24.0 degrees Celsius. Actual Evaporator Temperature (G263)
The temperature is 21.5 degrees Celsius. The ambient temperature, often known as G17, refers to the temperature of the surrounding environment.
The engine speed, measured in revolutions per minute (RPM), is sent across the Controller Area Network (CAN-Bus) at a rate of 800 per minute.
0.0 Compression. Status of Torque Signal
The compressor torque is 0.5 Nm.
The request for the Radiator Fan (V7) is 0.0%.

POSSIBLY UNRELATED: The Electronic Control Unit (ECU) continues to exhibit a defect with the AC pressure sensor that has persisted for over a year. (This is from the time when I began disassembling objects a year ago, but I had to activate the ignition once.) As I have not yet driven the vehicle, it is possible that this issue is only a distraction and will be resolved after a specific number of drives or starts.

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The address for the Auto HVAC system is 08. The labels for this system are identified as 420-820-043.clb. The software part number is 420 820 043 G and the hardware part number is also 420 820 043 G.
Component: J255 Climate Control System, Single Zone, Code 0100
Version: 00H06007 Identification number: 00000001184951
Coding: 1572906
Shop number: WSC 02197 785 00200 Vehicle identification number (VCID): 0E1386C619CC90E349-805A

The code 00256 refers to the A/C Pressure/Temperature Sensor (G395). The lower limit has been exceeded, resulting in intermittent freezing. Structure:
Defect Status: 00100010
Fault Priority: 3 Issue Frequency: 2 Counter reset: 121
Mileage: 31,162 kilometers Time Indication: 0

May we begin by examining the specific configuration you are using for the charging process? Are you referring to the manifold and gauge set that you are now using, as well as the R-134A refrigerant?

The VF kit relocates the high side valve. The reason it is located there is because of that, I assure you. )

Understood. I have a strong dislike for the little cans due to their incorrect use, tendency to be overfilled, and difficulty in charging. Particularly at low temperatures...

Initially, it seems that your little cans are incapable of generating a pressure beyond 75 psi on the lower side. This pressure limitation is due to a balance between the system and the can.

To activate the compressor on a Chevy truck, I would separate the low side pressure switch harness and connect the terminals to provide power. Although this situation is different, the underlying principle remains the same, and it is important to note that there is oil in the system.

I own a 30-pound item that is both new and sealed. You may choose to open and charge it if you like, and I will retrieve it at a later time. In my opinion, your outcomes are likely to improve, and I suggest beginning with this approach as a priority:
Revise: Heat the water and submerge tiny cans. Test the cans while they are warm and observe whether there are any variations in the PSI findings. If the compressor is on, the system will assist in creating a hoover to draw in the little cans.

Thank you much, @AudiFan2021. While I am grateful for the offer, I am uncertain about the process of accurately gauging the appropriate quantity of refrigerant, namely 680 grammes, that I would need from a 30lb tank.

This will likely be the one aspect of the project that I relinquish and delegate to Makes & Models after all other tasks have been completed.

Using a digital scale.

What was your plan for doing it with the little cans?

It's great to know that you are accepting it!

Equipped with a digital scale that has a maximum capacity of 11 pounds. I appreciate your offer once again.

It seems that you are in close proximity to achieving your goal. Congratulations!

I always despise it when individuals start discussions seeking assistance but then fail to provide updates after they have resolved their issues. I am astonished that I have transformed into "that individual."

Regardless...

I brought it to my nearby specialty store for rare and unique items, and they easily refilled it using their regular equipment and setup.