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  #1  
Old 09-15-2002, 09:41 PM
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Join Date: Jul 2002
Location: Stony Brook, NY
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Still trying to get a/c compressor to engage and still 1 KLIMA question

My car is a 1988 300SE and, oh, how I wish my first problem could be fixed!

The problem is still the same, the a/c compressor will not engage. I pulled the KLIMA relay and jumped #5&7 and it engaged. I took the relay carefully apart and cleaned it well with a circuit board cleaner and then hit it with compressed air. I checked the solder joints and all looked OK. I put it back in the car, started it up and still no engagement of the a/c compressor.

I did notice that on the KLIMA relay has one male rod labeled "T" and it goes into hole #12 on the board or whatever you call what the KLIMA relay plugs into. I noticed that hole #6 in my board has nothing for the rod on the relay to connect to, it's simply an empty hole. Can anyone tell me if there is supposed to be a female connection in hole #12?

I have looked allover the place around the "board" and I cant see any wire that could have slipped out. In fact, I can't even find a way for a wire to have slippe dout in the first place.

So, can any say if there is supposed to be a connection in hole #12?

Also, is there any other way for me to determine if the problem really is the relay. I really can't afford to spend over $350 to change the relay only to find that's not the problem.

The belt is tight and I can't turn the alternator by hand (someone posted this is a simple approximate test to see if the belt is too loose). Also, my wife used the a/c twice in the past week and it was fine, now suddenly nothing.

Thanks,

Ron B.
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  #2  
Old 09-15-2002, 10:15 PM
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Join Date: Dec 2000
Location: Fairfax County, Virginia
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My 91 350 SDL also has a Klima (likely same set up as yours).

First noticed I had lost the Klima when both the AC and tachometer went out ... I took relay apart, cleaned it, carefully pried points apart (mine had three sets), reheated several of the solder joints and tried it. Worked for awhile, then went out again. Did the same thing again, but filed the points a bit. Back in and it worked again ... still working.

During the time when it didn't work, I was able to get it to work by schwacking it with a heavy wrench ... not elegant, but when it was 100F outside ... well ...

I found rebuilt ones with year guarantee at Beckmann Technologies (advertised in The Star) 800.742.1021, but have not yet ordered one as I am not finished playing with mine, yet.

Mine has a missing pin and connector, as well. I have been unable to find any other issues except the Klima that accounts for the problem.
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George Stephenson
1991 350 SDL (200K and she ain't bent, yet)
former 2002 E320 4Matic Wagon - good car
former 1985 300 CD - great car
former 1981 300 TD - good car
former 1972 280 SEL - not so good car
a couple of those diesel Rabbits ...40-45 mpg
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  #3  
Old 09-15-2002, 11:16 PM
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Ron, You DID say that you had somebody checked that you have enough refrigerant in the system, right??????
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  #4  
Old 09-16-2002, 01:17 AM
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Did you check the conection at the compressor? I had a similar problem and it eneded up being a bad conection. I just put a drill into the little conectors and squeezed them a bit, put it back together and voila.... COLD air in TX. Just a thought.
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  #5  
Old 09-16-2002, 03:19 AM
RSH RSH is offline
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Klima stuff

I saw this on another site, Have you checked the 105/115 temp switch that sends info to the klima? when the switch goes bad sometimes it grounds out, replicating a overheat condition and telling the compressor to shut off, It should be located close to the coolant temp switch, disconnect the 105/115 switch and see if the a/c will operate.good luck
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  #6  
Old 09-16-2002, 10:13 AM
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Location: Cumming Ga.
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Starting in 1988 the "T" connector on the relay is no longer used. On previous years this was the input from the coolant temp switch. The temp cutout is controled by th ACC pushbutton control panel on the 88 year model.
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  #7  
Old 09-16-2002, 11:05 AM
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Location: Stony Brook, NY
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Stephenson: My tach has been working fine all along. That's the one thing that has made me think the problem is somewhere else. I will check out Beckmann Technologies if I need the relay. Do they have a website by any chance?

Piotr: I am assuming the system is fine poundage wise as I had it checked and filled the day after I bought it. I'll have it checked again this week.

davidmash: I'll pull off the connectors at the compressor. I doubt this is my problem as if I jump the board connection 5&7 the compressor does engage. My problem seems to be something stopping the signal form getting to the compressor.

RSH: I have to ask. You said the 105/115 temp switch is near the coolant temp switch. Where is the coolant temp switch?

RPM55: Thank you for your reply. At least now I can rest assured that I don't have a missing wire.

Thank you all for your time on this problem. I'm only glad summer is over. But it was very humid this AM and I would have loved to have the use of my a/c. I start with checking out the 105/115 switch (once I find it), then clean the relay contacts well. I'll have the system pressure checked. If all that fails and the connections to the compressor are good, I guess I'll have to bite the bullet and buy a KLIMA.

I'll keep my fingers crossed. If anyone can tell me where the 105/115 switch is or even where the coolant temp switch is it would be greatly appreciated.
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  #8  
Old 09-16-2002, 12:00 PM
RSH RSH is offline
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Klima stuff (105/115 switch)

The manual says it (105/115 switch) is located at the top front of the engine, In the picture (which isnt very good) it looks to be in the area of the upper radiator hose outlet on the engine and in front of the air cleaner housing, The regular coolant sensor is located in the same area.
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  #9  
Old 09-16-2002, 12:24 PM
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Thanks! I'll print this out and check it out this evening. I hope this is it. It has to be a lot cheaper than the 350 Klima.
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  #10  
Old 09-17-2002, 10:57 PM
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I was able to jump mine as well but the conection was bad enough to interupt the signal from the compressor. There is something that tells the computor that the engine is on and the compressor is not slipping. The bad conx effected that and the a/c would shut down and not come back on till you shut down the engine and restarted it.
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  #11  
Old 09-18-2002, 03:39 PM
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Location: Fairfax County, Virginia
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Klima, I have been told, tells computer compressor clutch is spinning and the engine is running. i.e. is clutch stops due to seized compressor, with the engine running, the computer declutches to keep the single serp belt from burning up ... appears this was to prevent loss of end state driveability with the move to the newer serp belts (older models had two belts, if I recall).

Klima can be bought rebuilt for about $50 or so, I think.
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George Stephenson
1991 350 SDL (200K and she ain't bent, yet)
former 2002 E320 4Matic Wagon - good car
former 1985 300 CD - great car
former 1981 300 TD - good car
former 1972 280 SEL - not so good car
a couple of those diesel Rabbits ...40-45 mpg
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