1950s 1951 Seventy-Five: purpose of a knob

[Roger Zimmermann]

On the left side from the instrument cluster from a 1951 car, there are two knobs: the upper one is for the wipers. What is the purpose of the round knob just under the first one? Sorry the text is in German...
The owner's manual is published in the Heritage Center; both 1951 and 52 manuals are very discreet about this knob: I saw no explanation.

Schalter Armaturenbrett.pdf

Thanks for the help!

[V63]

Someone will surly know this but it got my curiosity 🤣✅

The owners manual suggests two possibilities, fog lights or convertible top. See images

[Roger Zimmermann]

That's! As the car is a closed one, the knob can just turn but not be pulled!
The fog lamps are just under the knob for the convertible as stated in the German attachment.
Thanks for the explanation; this morning I did not see the page for the convertible operation.

[V63]

Well what ever it is ...convertibles don't have it 🤣✅

[Alan Harris CLC#1513]

Many years ago, I had a 1951 Series 62 convertible. That knob was for the power top. On a Series 75, I would bet that it is for the divider window.

[Roger Zimmermann]

Many years ago, I had a 1951 Series 62 convertible. That knob was for the power top. On a Series 75, I would bet that it is for the divider window.

Thanks Alan. I had also that idea, but I'm not sure if the driver has the possibility to open or raise that divider window. I'll ask the man who wanted to know the purpose from that knob.

[V63]

I echo that i would not anticipate the driver would have control of the division.

Best to see what's 'behind' the switch? Wires? Or cable or vacuum hoses? Or nothing?!Maybe it's a dummy filler knob?

[Roger Zimmermann]

That would be also my first step. However, some people prefer to ask first! On the other side, I don't know if it's easy to see what's attached to the knob...

[V63]

You would probably need to stand on your head but it's not that encapsulated otherwise

[Jay Friedman]

My guess--and I emphasize it is a guess because I don't own a '51--is that it is for the fog lamps.  My reason is that on my '49 a similar knob has that function. 

[Roger Zimmermann]

Jay, no, the knob for the fog lamp is under that mysterious knob. I gave your thoughts to the owner, up to now he is silent...

[The Tassie Devil(le)]

You would probably need to stand on your head but it's not that encapsulated otherwise

No need to stand on ones' head.   Deftly position a mirror and look in comfort.

Bruce.

[Roger Zimmermann]

Strange people sometimes...The man who asked me about the purpose of the knob found the answer from his documentation: it's to fade the radio in the back.