Just finished putting in a used Climate Control servo I bought from a forum member here, burped the cooling system and started to test it out. The servo I bought was a 104 model, my car had a 102. The only difference between the two is the potentiometer wheel resistances. I think the servo, and sensor chain are working, because I hear the servo motor park, and the motor runs when I move the temperature wheel, the servo motor runs as well.

When I move the wheel to 85 degrees, I get dash-melting heat. When I move the wheel to 65, I still get heat, so I need to adjust the wheel. The air compressor is running since I can only use the defrost button.

Only defrost works currently... There is a massive leak in my climate control, no other buttons work, and my engine will not shut off if left in auto high, low, or bi-level. I think it's a switchover valve or the push button panel, it worked last summer, but kept getting slower until the blower turned on, eventually the buttons did nothing.

I'm going take off the console and try to test some of the components. How would I adjust the temp. wheel when it's on the car, or do I have to take it out?

Here's what the manual says to do. Think the MB dealer or anyone here has the "adjusting wrench?" I probably won't get too many responses on this but it's worth a shot since I couldn't find how to adjust this using search.

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1980 240d
1999 SL500

I had a 1981 Wagon with that system...
Now you know why I own a 1980 240d with the prior system...I have looked at the manual for it...amazing...
It sounds like you need to pull it out of the dash far enough to get VOM clips to each side of the potentiometer ... and disconnect the temp sensor on the dash... and measure where that sensor sends its readings...

Bump, anyone know how to adjust it? I'll probably have to take off the console.

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1980 240d
1999 SL500

Even then I don't know if anyone can help you....
I suggest you keep it together and fix your vacuum leak first..
I have the MB FSM for AC... it is a bear... but I am sure that without the vacuum in the car working you have no way to test out the other stuff...
Have you ever seen the schematics for this system ?
The flow charts for diagnosing ? If you had you might have waited for an exact match on the parts....
I will attempt to help... but I am saying up front that this type 2 or type 3 system is beyond my comprehension level. I do pretty well with the manual system which preceded these ....
Work first on determining why you only have defrost to choose from... and take an aspirin before starting to work on it.... I will do the same here...

When my 77300D was fairly new the dealer took something like that tool and went in beside the temp wheel and adjusted the temp. I have since replaced the servo with an electronic unit, but still can take a putty knife, with the wood removed and move the wheel adjustment until it is colder or warmer, based upon my wife's current temp needs, not complicated at all. You are going to have to fix the vac leaks before you can do any of this, if all you are getting is defrost, you have some serious leaks.
ron

Well, I fixed the leak, an actuator (one directly behind the left side of the glove box) was ruptured. I plugged the line with a golf tee and now I have blower functions again. Also, my vacuum locking driver's seat works now, the transmission shifts smoother, engine shuts off faster. The servo does work, I can move it to 85 and get heat, back to 65 and get cooling. Pretty cool system when it works. A putty knife works at adjusting the wheel? I think I'll try that, I assume that one or more switches need to be removed to pull the wood off? I think a P.O re-glued the wood sometime ago. Thanks for the responses.

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1980 240d
1999 SL500

HEY, That was easy !!
Congratulations...

Finally, one of my projects on this car didn't take me 4-8 hours like the shocks and upper control arms. The flap that's ruptured is the main air flap, not sure what that does. And I now have a smoother shifting transmission, blower, engine shutting off faster, vacuum locking coupe driver's seat (passenger's seat lock has a leak) just from fixing that one leak. Cool stuff!

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1980 240d
1999 SL500

For Sure !!! These cars are NO FUN without vacuum....LOL