Was driving and smoke started coming out hood. Pulled over and shut off car, and it wouldn’t turn back on. Waited a little bit longer and message showed up saying you can now start car and car started fine. Towed car straight to dealer none the less and dealer found no problems, picked car up from dealer and driving home realised it had no ac. Bought a AC reload can and gauge showed in red im assuming it’s not freon. Any ideas ?

2012 ML 350 Bluetec

 

Could be the "smoke" was actually the refrigerant charge blasting out of the system from a catastrophic failure of a line or seal.