Intermittent AC problem

[paulfoel]

Had it re-gassed a year ago.

The other day stopped working. Then it started again and has been off/on ever since. Display shows AC on. Also, when Iturn it off I can hear it starting every time.

Took it to garage. They said machine showed ZERO.
They want me to take it back tomorrow so they can use nitrgoen to check for leaks.

What does machine actually do? There seemed to be some sort of printout.
Surely if the coolant was down to zero it wouldnt work at all ever?

[JohnHere]

Vehicle year, make, model, and engine size will help us help you to diagnose this.
Question: Since you took it back to the shop and their machine showed 'zero,' does the compressor run anymore?

[paulfoel]

Vehicle year, make, model, and engine size will help us help you to diagnose this.
Question: Since you took it back to the shop and their machine showed 'zero,' does the compressor run anymore?

Ford Galaxy 2010 1.9TDI Diesel. (Im in the uk).

Yes it worked for a bit now stopped again.

[JohnHere]

Since we don't know what the pressures are, I wonder if by 'zero' the shop meant that they were very low. Hard to tell from across the pond. But if that was the case, I would begin by recovering whatever refrigerant might still be in there, then evacuate and recharge with the correct amount of R134a. At the same time, I would add a little UV dye and proceed to leak-check the system. More than 60 percent of mobile A/C problems are due to leaks, so you might as well begin with the most likely cause. Be sure to check the condensate tube underneath the vehicle for the presence of dye, too, which might indicate an evaporator leak.