There is no "standard" for pressure when the system is OFF. You can only take meaningful measurements while the system is running. The figures you have quoted are general. For you specific vehicle you should look at the service specifications which will tell you the pressure ranges based on outside temperature as well as the refrigerant charge.
(Copying my previous comment here as I do not know if the poster to whom I am replying get notified if I am posting a comment, as opposed as a reply)
Thank you for your prompt reply. Could you please clarify where is that part that moves "on the backside of the expose part"? Is the part that moves part of the coil/pulley/clutch, or is it inside the ...
You can't normally press on the outer portion of the clutch and have it engaged. The part that moves is on the backside of the exposed part. The entire clutch plate doesn't move, just the inner part that contacts the pulley.
To test it with the engine off, you can apply 12V to the coil and you should hear it engage. If not then you have an issue with it.
In answer to your question, NO, you cannot use a standard vacuum pump to recover the refrigerant from an A/C system. They are not designed for this purpose and will not do what you need it to do.
A HVAC recovery system is design to pull the existing refrigerant out of your vehicle and them pump it into a receiving tank. It's essentially two pumps in one. A ...
You should evacuate the system, then establish a depression on it and leave it to find any leaks.
If there are no leaks then the manufacturer will state the amount of refrigerant and oil to be added.
You stated in your question that it requires 135ml, so remove any oil still in the system then add that amount.
The systems used by both my garages (one in UK, ...
In most systems, and I'm sure your LR4 is typical, there is a low pressure switch that will shut off the compressor after a minute or two if there is too little refrigerant in the system. After another minute or two it will cycle back on and the process repeats. This mode of operation doesn't provide much cooling and, as you noted, it seems to work for a ...
Yes, you could easily have a large leak. The most likely place is Corrosion on the condenser (next to your coolant radiator at the front of the car).
I would have thought that you should be able to hear the gas escaping if you get your ear close to the condenser.