2003 Volkswagen Golf Compressor not starting

Hello,

I was on a road trip when my AC stopped working. I took it into a repair shop and then did a few tests. The checked to make sure the system was charged and had no leaks -- everything passed fine. They told me it was the compressor that was not starting. They said they had narrowed it down to the either the AC's ECM or the switch that were not kicking in to start the AC compressor.

Does anyone have any ideas/suggestions?

The car is a 2003 VW TDI Golf 1.9L, manual.

Thanks,
Peace,
Shaffy