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Old 02-05-2014, 04:33 PM
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JamesDean JamesDean is offline
Electrical Engineer
Join Date: Apr 2005
Location: NE Ohio
Posts: 5,038
Originally Posted by funola View Post
I got confused by your: "The first gen 126 and 82-85 123s used these style of climate control systems."

My 83 and 85 123's climate control system does not have IC's AFAIK. If they do, please let me know which box they are found in. I know my PBU's does not. Are there other 123 climate control boxes with IC's that I am not aware of?
Ah! Now I understand. And you're right the PBU doesn't but the PBU interfaces with two other control units.

The climate control system used on the 126's and 123's in the early 80's consisted of three boxes:

1) push button unit
2) blower motor control unit (on 126 located left side of passenger foot well on blower box)
3) temperature regulator unit (on 126 located right side of passenger foot well on blower box)

The last two units do have some integrated circuits in them as you can see from the pictures that I posted above.

These only apply to cars with the automatic climate control system of course.

The pbu sends out control signals to these boxes and they act accordingly.
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