Hello everyone,

Forum member mccauleybil sent me his climate control unit to see if I could repair it.

He sent:

126 830 02 85 Climate Control Push Button Unit
126.032 - 380SE
126.033 - 380SEL
126.037 - 500SEL
126.043 - 380SEC
126.044 - 500SEC
126.120 - 300SD

000 822 09 03 Temperaturregler.
126.032 - 380SE
126.033 - 380SEL
126.037 - 500SEL
126.043 - 380SEC
126.044 - 500SEC
126.120 - 300SD

I took apart the PBU and discovered that there really isnt much to go wrong inside this unit! There are a few relays, diodes and resistors and thats it!

What I did see that could go bad are a large amount of solder points on the back.

The temp setting wheel also contains some interesting circuitry. There is a small 10k pot mounted at the center of the wheel. There are also three traces that the unit uses as a potentiometer as well. Now from all the other trace style pots that I've seen there has always been a carbon coating present, however this was not the case. I'm not sure if its simply eroded away over the years or simply was never present in the first place... I dont have another PBU to disect for comparison.


PBU Pictures:

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(4/11/2020: Hi Everyone! I am still taking orders and replying to emails/PMs/etc, I appreciate your patience in these crazy times. Stay safe and healthy!)


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