According to an Ex VW Mechanic I know, he says they were told to run the diagnostic, and whatever sensor shows up as causing the problem, replace it - no matter how many sensors and whether they are faulty are not.

All the costs are passed onto the customer, which they have to pay to get their car back so the Garage never loses out.

Shocking really.

He has retired now and looks after our 2 Golfs, but any diagnostic work he does he does "properly", sometimes you can simply reset that fault and things are fine sometimes it really is a sensor.

Other halfs Golf went into "limp" mode a while back, he just cleared the fault and it has been fine ever since.

Sometimes sensors throw a fault when there is nothing wrong with them.