Hello....this sounds exactly like the problem I am having with my wife's ML320. I know its a short somewhere in the fuse box because up until two days ago, when the compressor would refuse to come on, I could tap on the fuse box and the compressor would miraculously wake up! We had done this for the past year....but I guess the short is in a position now where a tap will not work any longer. Can you please describe how I could check to see if something is grounding out under the fuse box? Also, I know about the F44 fuse, and that fuse is not blown....I checked it, and it is not blown, but there is a relay that clicks when it is taken out and reinserted....K19...I do not know if this is where the short might be....has anyone attempted to lift up the fuse box board to reseat or check wires????? Please post or email me if you can provide any help. Thanks...I am letting wife use my S320 right now, and I would like to get hers fixed so I can get my car back.

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1994 S320
131K miles

1998 ML 320
126K miles

1994 Blue C220
122K miles

Im going to Grad School @ the University of Iowa
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