The real question is whether or not the a/c controller is telling the BASE module to turn the compressor ON or not.

IF the BASE m,module has codes about belt slippage OR clutch operation blocked, it won't try to turn the compressor on.

Can you read codes from BASE module? OR does someone have scanner that can look at live data in that module?

__________________
MERCEDES Benz Master Guild Technician (6 TIMES)
ASE Master Technician
Mercedes Benz Star Technician (2 times)
44 years foreign automotive repair
27 Years M.B. Shop foreman (dealer)
MB technical information Specialist (15 years)
190E 2.3 16V ITS SCCA race car (sold)
1986 190E 2.3 16V 2.5 (sold)
Retired Moderator