tiny indicator bulb inside fan motor control knob

[n/a]

In the very centre of the interior fan speed control knob (fan rheostat control) on my '64 230SL is a tiny bulb which is supposed to light up whenever the fan is in operation. Do these ever work? Mine doesn't. Has anyone found a source for the bulbs and/or can offer their experience on replacing the bulb? any contact much appreciated!

[Mark in KS]

Yes, the switch has a light that works.  Check your normal supply sources for a replacement bulb.  The illumination is actually not real bright.  Yours might be lit, it's just very dim.  Look at it straight away in a dark setting to determine if it's really working.

[jlennon3]

The MB part # is 001 544 0194 off an old package of this light bulb. The package looks really old though, so part # may or may not still be good.

Good luck
John

[hands_aus]

Hey aussie230sl,
Grime can block the little hole of the knob too.
The light bulb fits into the base of the rheostat. Have you checked the connections to make sure there is continuity?

I think the bulb is held in place by a metal clip rivetted to the body and can be rotated.
You rotate the clip aside enough to remove the bulb then clean everything to create good contacts and then try your old bulb (after cleaning its contacts too) before installing the new one.
It is a very low wattage bulb, something like 3Watts, could be 4 Watts.

My light works but it is barely visible unless I look directly at it.

I think there was a discussion about these bulbs a while ago. If you do a search from this page on Fan switch etc you will find something to read.

Where in Oz are you?

Bob Smith (Brisbane,Australia)
RHD,1967 early 250 SL, auto

[n/a]

quote:Originally posted by hands_aus

Hey aussie230sl,
Grime can block the little hole of the knob too.
The light bulb fits into the base of the rheostat. Have you checked the connections to make sure there is continuity?

I think the bulb is held in place by a metal clip rivetted to the body and can be rotated.
You rotate the clip aside enough to remove the bulb then clean everything to create good contacts and then try your old bulb (after cleaning its contacts too) before installing the new one.
It is a very low wattage bulb, something like 3Watts, could be 4 Watts.

My light works but it is barely visible unless I look directly at it.

I think there was a discussion about these bulbs a while ago. If you do a search from this page on Fan switch etc you will find something to read.

Where in Oz are you?

Bob Smith (Brisbane,Australia)
RHD,1967 early 250 SL, auto

Many thanks for that comprehensive reply! Melbourne here.

[Naj ✝︎]

001 544 0194 supercedes to 000 825 0094.
Real wierd looking bulb.
Me not seen one.
According to my parts book, a normal 12V 2Watt BA9s bulb (as used in other dash instruments) is fitted. MB N 072601 012800.
Best to have a looksy which one you have.
naj

65 230SL
68 280SL

[ja17]

Hello,
Here is a cross refference chart with some Osram and Dr. Fischer part numbers for bulbs. Click the "enlarge button" so you can read the numbers. (third post from top "Mercedes Light Bulbs jpg")

http://index.php?topic=1048

I believe figure #10 is correct. Also #11 is the same size except with higher wattage !

Joe Alexander
Blacklick, Ohio

[n/a]

Try MB DIN # 072601-012230. Really small bulb, no metal base. The one mentioned in previous threads is the same size, but frosted.

Tom Hanson
Parts Manager
MBUSA Classic Center
Irvine CA

[JPMOSE]

I just replaced the knob on my fan switch.  I don't see any light when switched on.  Do all models have a fan switch light?  My car is a late 250SL (1968 model).  My old knob had a small hole in the middle (this could have been drilled by the prior owner for all I know)...did the original knobs have a hole?  Thanks.

Best Regards,

J. P. Mose
1968 250SL

[Naj ✝︎]

JP,
here's a picture of my blower switch from a 230SL. Don't know if they were used on the late 250s. Did you see the clear plastic bit when you had the knob off?

The bulb (same as other dash lamps) goes on one side and the light shines thru the clear plastic bit sticking out thru the spindle (and the hole in the knob).

A replacement plug [014 545 8528] is also pictured. Fits on the clock and blower switch and maybe other places?? Maybe not for the purists :x


Download Attachment: Htr_Blwr17.JPG
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naj

65 230SL
68 280SL

[rwmastel]

quote:Originally posted by JPMOSE

Do all models have a fan switch light?  My car is a late 250SL (1968 model).

I would assume this light was removed when the interior knobs (radio, fan speed, cigar lighter, window cranks) changed shape.  I assume these changed shape at the big early/late 250SL change.

Rodd
Powell, Ohio, USA
1966 230SL, Euro, Auto, Leather, both  tops
1994 E420

[drewsalisbury]

Tom - does this mean that you are open for business?

Tom Hanson
Parts Manager
MBUSA Classic Center
Irvine CA

Drew Salisbury
1971 280sl auto