My A/C was working this morning, now it's no-go.

The compressor is not engaging. It was getting dark as I pulled up to the house, so all I was able to do was check fuses and wiggle them all, ensuring they are all seated properly. I'll take a closer look tomorrow morning but figured I'd throw this thread out there to see if anyone can speak to the common trouble spots on this car (I haven't done much A/C work on it thus far other than charging).

First thing I'll do in the AM is check the charge to make sure it's not too low, but I don't expect that to be a problem.

Are there any relays or anything connected to the climate control panel that I should be checking as well?

Thanks in advance!

__________________
08 W251 R350
97 W210 E320
91 W124 300E
86 W126 560SEL
85 W126 380SE Silver
85 W126 380SE Cranberry
79 W123 250
78 W123 280E
75 W114 280

Oh yeah, I'll check to make sure the power leads to the compressor are still attached. I do recall about a year ago one of them fell off which resulted in no A/C. I had to put a new female spade connector on there, and it held fine. Incidentally, I did change the oil this morning - I wonder if I knocked one of the power leads loose while crawling around under there?

Anyway, if anyone has any other suggestions please post it here. TIA!

__________________
08 W251 R350
97 W210 E320
91 W124 300E
86 W126 560SEL
85 W126 380SE Silver
85 W126 380SE Cranberry
79 W123 250
78 W123 280E
75 W114 280

Bump - just went out there and checked a few things.

A/C compressor rotates freely. System has sufficient refrigerant charge (50 psi both sides). With engine running, when I press the A/C button on the control panel the compressor "attempts" to engage intermittently, for a split second here and there (no rhyme or rhythm to the attempts, just random). Watching the gauges, the pressures barely move 1 psi on either side as the clutch just cuts out as quickly as it started. So whatever it is, the clutch just does not want to remain engaged.

It is 55 degrees here - I certainly don't think that's "too cold" for the system to engage, is it?

Any ideas PLEASE?! I'm taking this thing on a road trip tomorrow and it's going to be rainy, so I need to make sure the A/C works.

__________________
08 W251 R350
97 W210 E320
91 W124 300E
86 W126 560SEL
85 W126 380SE Silver
85 W126 380SE Cranberry
79 W123 250
78 W123 280E
75 W114 280