It was working and blowing cold air, albeit a bit loud, and now is kaput? Is he a professional or a shady mechanic. Changing compressor is easy and it seems he has all the tools. Ask him how he charged the system and got all the pressure 'correct'? How could he do it without the compressor ever engaged? It does not make sense.

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Not MBZ nor A/C trained professional but a die-hard DIY and green engineer. Use the info at your own peril. Picked up 2 Infractions because of disagreements. NOW reversed.

W124 Keyless remote, PM for details. http://www.peachparts.com/shopforum/mercedes-used-parts-sale-wanted/334620-fs-w124-chasis-keyless-remote-%2450-shipped.html

1 X 2006 CDI
1 x 87 300SDL
1 x 87 300D
1 x 87 300TDT wagon
1 x 83 300D
1 x 84 190D ( 5 sp ) - All R134 converted + keyless entry.