2009 ML350 A/C Related Fuses

The truck A/C air was gradually warming, took it in for a recharge and told it was blowing cold. When I picked it up the air was barely cool and it seemed like the compressor wasn't on. When the A/C is blasting I can feel the truck shaking slightly when stopped at a light. Took it back, put it on th machine, not overfilled, balanced properly and they say the compressor must be rotten on the inside and $1700 for the entire job.
I plugged in the scanner at home and no codes.
Is there a datastream that I should check?
I plan on taking it in to my mechanic next week to diagnose but was hoping to check the basics myself hoping it's something simple.
Thanks in advance for everyone's help.


