Check the 30-amp strip fuse on the driver's side strut tower. The fuse is inside the black plastic enclosure. Typically the fuse develops a hairline crack that becomes obvious when you remove the fuse.

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Fred Hoelzle

This fuse is in the main fuse box or under the plastic surrounding the fusebox?

Normally the 30-amp strip fuse is in a small (approx. 1" x 1" x 2") black plastic enclosure atop the driver's side strut tower in front of the main fuse box.

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Fred Hoelzle

Found it thanks. I removed the screws and the fuse, it appears to be intact.

For issue #1 I would look at the ignition switch. I had the same problem and I noticed one day when I wiggled the key with it running the blower came back on!.............Worth a try

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88 W124 3.0
96 R129 119eng
06 ML350
98 ML320 sold
02 CLK55 amg

Well good news the mono-valve replacement fixed the problem. The A/C is now ice cold from all vents.