Where and how do you refill freon on a VW 2001 Jetta?

low or no freon---- compression problem

try to throw cool water on the condencer front of the engine radiator and see whether any cool air comes in the car. If so see whether the pressure valve is working okey or not because might the pressure is not sufficient.

IS THE SYSTEM FULL OF FREON? IF ITS LOW THE A/C CLUTCH WILL NOT ENGAGE. ITS KIND OF LIKE A FAIL-SAFE FOR THE SYSTEM. IF THE FREON IS FULL AND YOU HAVE 12V TO THE COMPRESSOR I WOULD CHECK OUT THE CYCLING SWITCH ALSO.

check high pressure with a proper machine and see how many bar you have ,think compressor may be on the way out .

the fan control unit at front r/h chassis from down or flow fan motor cable it;s conect with control
A/C pressure S.W look to two freon hoses gose to body if you folow you find the presure s.w conect with socet 3 wire can be replace without lose freon .

If freon is low, AC will not engage. There's a low pressure safety switch incorporated in compressor so it doesn't burn up under low pressure condition. Have system evacuated, refill w/oil & freon

The bigger question is how did it lose the Freon to begin with. You can get R-134a at most parts stores and the fitting on the refill cans will only fit on the low side but if you don't fix the leak it will just go low again. try auto Zone for a refill or booster can if you are looking for that.

You may not be full of refrigerant... There is a low pressure switch that prevents the AC from actuating the clutch, and the reason is: IF there is not enough refrigerant, you will not be able to move oil through the system and you will have major damage...so no engauge...

Get the system checked, most likely there is a leak somewhere..

by cut off, do you mean it turns off, or stops pumping out cold air? If it stops pumping out cold air, definitely sounds like you have a freon leak. If it's turning off completely, it could be the switch is just acting up, or it could mean the condensor is going bad

Unfortunately I am aware of no pictures or diagrams. There are two connections, a low pressure and a high pressure connection. The high pressure connection is found between the engine and the firewall. The low pressure connection is in front of the engine along the inside lip of the hood closure. As you open your hood, it's located just in front of your lefty knee. The connection is on an aluminum tubing, and mine has a black screw cap on it. Not sure if the cap varies in colors, or whether your may have been removed. The connecting hose from your freon refigerant H134a will ONLY fit onto the low pressure connection. The charge is just a bit more than 2 pounds of freon. In a 2001 you may need to add more than i can if the car has never been recharged, but start with one can and see how it goes. You may also want to add a freon with a sealant just in case you have a small leak. One can is approximately 13 ounces.