Gentlemen so can't quite agree with what you write.... often the descriptions in the VCDS of course I mean the original tester has errors in the numbering of the exhaust gas temperature sensors.... it is not at all that difficult to give a wrong reading of what the tester describes.... even VW itself had errors in the descriptions and this was in both the VAS 5054 and the first Odis.... on this subject there were several TPI service bulletins issued by VW which "straightened out" the errors in the diagnostic software.... on 1.6 tdi engines and some 2.0 tdi PQ platform engines, the manufacturer introduced an update of the engine controllers, because the engine controller itself already had a so called error code mapping error.... unfortunately having good equipment and "trusting him" you can get run over, that's why I would be far from a hasty assessment of this mechanic....
unfortunately, but modern diagnostics can be quite complicated, and if we add to this the errors in the software of car manufacturers themselves, with which even authorized service are often helpless, it is difficult to blame anyone that acted in accordance with the logic and indications of the computer .... even worse, without being aware that they are becoming a victim of underdeveloped software.... even the aforementioned multimeter won't help much if the temp sensor has a "temporary break" or worse a disturbed hysteresis, and in the ECU the sensor G235 is systemically swapped with G495....
