On a 124? I see an orange plastic dome on the switch, and I'm wondering if there's a light bulb back there somewhere that is burned out.

TIA!

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-Paul-
'01 E430, Sport 72,000 mi
'98 C280, 126,500 mi

It only lights up when you pull the switch out "two clicks" to enable the rear fog light.

If it doesn't illuminate, you can pull the switch completely off to reveal the tiny bulb that resides in the shaft. You need Keebler elves to get it out!

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2009 ML350 (106K) - Family vehicle
2001 CLK430 Cabriolet (80K) - Wife's car
2005 BMW 645CI (138K) - My daily driver
2016 Mustang (32K) - Daughter's car

The orange bulb inside the switch won't light on a '91 300E because I don't think the standard 300E had the rear foglight option. The 300E/TE 4matics have the rear foglight option, therefore the light will come on. The switch positions are backlit by a small light that is accessible by removing the knob, unscrewing the switch holding nut, and prying the plastic trim piece out. The chassis manual has a piece on this including a pic to show you how.

someguyfromMaryland

I had a 89 300E and it had the rear foglight, its safe to say the 91 does as well.

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1993 500E
http://2phast.com/500e/500e-sig.jpg

My 300E does have the extra fog lamp bulb on the rear driver's side, so I guess there is a burnt out bulb behind there.

I will disassemble and replace hopefully without the need of elves.

__________________
-Paul-
'01 E430, Sport 72,000 mi
'98 C280, 126,500 mi

If your headlight switch illumination is working, just pull out the knob without disassembling anything.

Otherwise, follow "someguyfromMaryland" advice...

__________________
2009 ML350 (106K) - Family vehicle
2001 CLK430 Cabriolet (80K) - Wife's car
2005 BMW 645CI (138K) - My daily driver
2016 Mustang (32K) - Daughter's car