I have a problem with my 89 190E 2.6L gas/auto.

The A/C compressor wont come on at all. Heres the story:

Bought the car, pulled the Klima relay, it smelled like burned electronic crap, i put it back on.) I hook up A/C gauges (cant stand that hi side connection port location) vacuum for .5 hour. Charge 2.2 lbs or R134a. Set controls for Sno-Cone and the compressor comes on for maybe 8-10 seconds, then shuts off. I pull the Klima, its still stinks (of course, its the old one) I take one off another 190E i have that smells delightful and I know that one works Hook it up to the subject car and the comp comes on for 8-10 seconds and conks out. I shut it all down and the relay stinks like burned electronic crap (yeah, the good one) So I pull apart the new and old one and see that the tracing on the board from pin 15 to the black side of Diode 1 is toasted. Both of them.
What gives?

I am considering a soldering repair. Can someone aid here. I dont want to burn new relays. PS I have checked the belt tension and it is super with a new belt. When the comp did run, it wasnt noisy.

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Ok. me again.

I went to braingears and looked at the tempmatic schematic. Turns out pin 15 is the positive voltage into the klima. I believe it was overloaded by a bad electrical coil on the ac comp clutch. I measure from pin 87 of Klima to ground, and got 0.07 ohms. I unplugged the 3 pin connector at clutch and it went open, replugged and 0.07 again.

That value sounds like a shorted coil to me, Please correct me if I am wrong. Oooo...you know what, I will go and test my other car, hang on....

EDIT: Yep....the other car was 4.3 ohms. Time to find a coil and a Klima. Learn from my mistake, dont smoke a klima, measure from pin 87 to the battery ground and see if the ohms are Ok. I will try to solder a short wire onto the board and see if it's ok. That thing ought to have a fuse in the top of it like the OVP. Suggestion...Hint, Hint.

PS - How do you get the clutch off the compressor? Can I do it laying underneath the car with the belt off?

Excessive draw from the clutch.. should be 4-6A static draw MAX!

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