Well last year I was having trouble with intermittent A/C operation which would also quit along with the tach. I traced it to a connector behind the battery which was no longer insulated and was grounding out on the battery tray. Everything was fine for a while, then the A/C started cutting out again, only occasionally and this time the tach is not affected. When it cuts out, shutting down the engine and restarting will fix it.
The compressor is two years old. Two weeks ago I took it to the dealer and they pumped it down and recharged to verify correct charge. They also replaced one of the pressure switches, the one right next to the drier.
Also, the engine temp is ok, never over 100C and usually 90C with a new fan clutch, T-stat, radiator and genuine MB coolant.

I don't know what to check next. I was hoping for some input from some of the A/C guys out there.

Thanks, Brian

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Brian
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