Volkswagen Repair: V.W. Passat 1.8T 06/2002 A.C. not cold, mitchel on demand, sanden compressors

Question
I,m a tech at a repair shop, the above V.W. came in for a re-charge.  Used the R-134 evac/recharge machine, added the required 600 G of freon, and still not blowing cold air.  Looked in our Mitchel on demand for the possibility of a bad relay.  The picture of the relays I printed out looked nothing like the configuration behind the fuse box which is located at end of drivers side dash.  Removed the panel under steering wheel to get a better look at the relays, and it's totally different.  All the fuses are good.  I don't know which relay is for the compressor clutch, which isn't coming on at all.

Answer
Hi there Ian;  I have some difficulty with diagnosis by osmosis, but I have an idea about this one.  I suggest starting the car, turning on the A/C(Max./Recirc.), then go to the front of the engine...if it's on a hoist, and the belly pan off even the better....raise it up running so you can look at the bolt head in the middle of the compressor.  The compressor will be engaged, and the electromagnetic clutch energized, and turning, but the bolt head in the middle of the compressor...Stationary!  The Sanden compressors used in the VW systems have a break-away feature.  If the "filter" at the back of the compressor builds up too much debris, the drive shaft of the compressor will break at the weak spot(designed), and the compressor will no longer operate.  Replacement of the compressor is necessary, as is a full system back flush with high pressure Nitrogen gas.  If you, and the shop are feeling lucky, you can replace the A/C compressor, and the accumulator dryer after the recovery of the refrigerant you added to the system today.  I have done this before, but had to make the call based on the rest of the car...nice, and clean, not a slob's car...if the same is true of your customer, the same pleasant outcome might happen for you, as well.  Rhetorical question...if you spell the middle word of' "M" on demand '   what do you get?.....something similar to "No Data!"?  Strictly rhetorical...and editorial..sorry.