Have done a little more digging ..
Vagcom thinks the compressor is running. Measuring Block 001 shows this based on the following label file. Mine shows 0, and then 6 if I press ECON, or 7 if I turn it off. When driving if I put my foot down it shows 12 , which is off for 12 seconds when requested by engine.
None of the obvious issues I was expecting a fault code to be flagged for so I wonder if the fault is with the Fan ?
001,1,Comprossor,Shut-Off,Specification: 0 = Compressor Running
; 0 = Compressor Running
; 1 = Compressor OFF by Pressure Switch (F129): Refrigerant Pressure too High
; 2 = Compressor OFF by Fresh Air Blower (V2) or Fresh Air Blower Control Module (J126) Malfunction
; 3 = Compressor OFF by Pressure Switch (F129): Refrigerant Pressure too Low
; 5 = Compressor OFF by Missing Engine Speed Signal
; 6 = Compressor OFF by ECON Button
; 7 = Compressor OFF by OFF Button (via Fresh Air Blower Speed Buttons)
; 8 = Compressor OFF by Ambient Temperature below 3 °C (37 °F)
; 10 = Compressor OFF by Voltage below 9.5 V
; 11 = Compressor OFF by Coolant Temperature too High
; 12 = Compressor OFF by Engine OR Transmission Control Module
; 13 = Compressor OFF by Voltage above 17 V
; 14 = Compressor OFF by Evaporator Temperature
; 15 = Compressor OFF by Control Module Coding incorrect
; 16 = Compressor OFF by Climate Control Module (J255) Malfunction
; 17 = Compressor OFF by Pressure Sensor Malfunction
001,2,Engine Speed,recognized,Display Range: 0 = no/1 = yes
001,3,Vehicle Speed,,Display Range: 0...255 km/h
001,4,Standing Time,,Specification: 0...240 Min | 250 = Battery disconnected | 255 = Transfer Malfunction