MAJJ

Hi everyone,
This is my first thread. I need help on the type of A/C compressor fitted on the 2012 GLK350 4Matic, is it clutch-less type, or with clutch? The problem I have now is that the compressor is not working. The AC system is charged with freon, but I get hot air only. I would greatly appreciate your feedback on the following:
1- I replaced the front condensor, but then drove the car for nearly 6000 miles without charging the AC system with freon (and oil). Could this have damaged the compressor?
2- Is there a way to test the compressor to see if it is still functioning?
3- Is there a control card/relay for the compressor? if yes, where is it located?

Thanks again for your feedback.

MAJJ

CarbonKevinYWG

1. The compressor should have a pressure switch that prevents it from running if the system isn't charged, so in that case damage is unlikely.

Was the system at evacuated (vacuum drawn) after the condensor was installed?

2. The way to test it would be to hook a set of gauges up to the two ports in the system while it's running to see the line pressures.

I guess the real question is what led you to need to change the condensor? Could other components have been damaged at that point, too?