Take the 4 screws out of the top of the mono valve, pullout the slug, and check the diaphragm.If it's torn, buy a replacement kit.
Chrysler sold the earlier ACC system to MB. It was about the same quality as the cruise control system Ford sold them in the early 70s.
Sorry. Yes. Climate Control Unit is samy same as Electronic Control Unit. CCU=ECU Yes, they fail, but so do the other components I mentioned.
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