The AC compressor on my 85 300TD will not engage even though the system is full. I have replaced the fuse in the fuse box, but the compressor still will not come on. Is there another in-line fuse? Any ideas appreciated!

Richard

Won't a bad pressure switch cause this too?

On my SDL, the compressor wouldn't engage due to a bad compressor clutch.

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Chad
2006 Nissan Pathfinder LE
1998 Acura 3.0 CL
OBK#44
"Pleasure in the job puts perfection in the work." - Aristotle (384-322 B.C.)

SOLD
1985 300TD - Red Dragon
1986 300SDL - Coda
1991 - 300TE
1995 - E320
1985 300CD - Gladys

bad RPM sensor, bad klima relay, bad air gap on clutch, etc etc etc... search klima diagnostic

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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

For starters, determine if you have power at the compressor. Then you will know if your problem is electrical or mechanical.

On my car, same year and model, I have to rev the engine to get the compressor to kick in- been that way for years.

Once I do that, it's fine. If I recall, there's a vacuum operated switch on the driver's side inner fenderwell that enters into the mix somewhere.

Of course, this is assuming you have enough refrigerant and good hi- low pressure switches.

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1968 230S Automatic, Elfenbein
1975 O309D Executive Westfalia Camper Bus, Blau/ Weiss
1972 280SEL 4,5 Dunkelrot
1966 VW Type 34 "Grosser" Karmann-Ghia
1963 VW 1500 Variant Pearlweiss
1969 VW Variant Automatic, Perugruen
1971 VW Squareback Automatic, Clementine Orange
2001 E320 4Matic Wagon- Our belated welcome to the 21st century! Polar White
1973 280SEL 4,5 Sliding Roof "The Bomb", Dunkelblau.

Found the problem: the OVP relay had a blown fuse. On the 85, the OVP relay controls the tach and the AC compressor. Maybe on the 84...not sure.