95 E420 - A/C compressor won't engage and aux fans never start. Bypassed temp and pressure switches and had mechanic check freon. Have read tons of posts but so far striking out. Compressor and fans turn freely by hand. All switches on ACC panel work, defrost and heat work. What relays and sensors could prevent both compressor and aux fans from engaging? I just bought the car so don't have any repair manuals (yet). Just rebuilt my power steering this past weekend (ugh) so ready to get this A/C fixed! Any help is greatly appreciated. Great forum, glad to be in such good company! Thanks,

Terry

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1995 E420 148K
1991 300D - RIP

Have you un-plugged the 3 pin connector at the compressor & checked for broken wires THERE? common for the signal wire OR speed sensor wires to break at that connection.

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Thanks for the reply Doc, so they usually break at/in the plug? I haven't found a wiring diagram for my model yet, what voltages should I find there and where do those wires come from? Thanks again!

Terry

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1995 E420 148K
1991 300D - RIP

Actually where the heck is the connection on the compressor? Oh well, cramped space is a small price to pay for the V8

Thanks again!

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1995 E420 148K
1991 300D - RIP

Not sure if the gassers are the same as the diesel but on my 95 there is a relay panel behind the fuse box. There is a green relay and a blue one. Both of them have a fuse on them. One is a 15 amp and one has 30 amp. The 15 amp blew on mine and the aux fan would not engage. Might be worth checking out.

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Yes I already checked the fuses and they are fine. I need to verify the compressor connection but looked briefly last night and didn't see it. It started to rain so had to call off the search. Hope to work on it tonight. Thanks for the suggestion.

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1995 E420 148K
1991 300D - RIP

Ok, I found the compressor connection in the online service manual, now to find it under the hood.

__________________
1995 E420 148K
1991 300D - RIP