I saw a Euro W126 manual AC control set that has three thumbwheels and 2 dials. I can figure out the outboard thumbwheels and both dials but what does the thumbwheel between the dials control?

Thanks,
Sixto
87 300D

Blower speed & air direction.
And does use a computer to control functions.

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I think they called that system "temp-matic"? It still had automatic temperature control (duo-valve instead of a mono-valve), but air direction and speed were manual.

-J

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Thanks, all.

My question is specific to the thumbwheel between the blower control and register selection dials. If the outboard thumbwheels control left and right cabin temperature, what does the center thumbwheel control? Rear cabin temperature? I've seen 126 manual control panels without the central dial. It looks like it's in a center 0 position. It's not 22 which would indicate a temperature control thumbwheel. Maybe an auxiliary heater?

Sixto
87 300D

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