What's the light on the light switch for? - PeachParts Mercedes-Benz Forum

jbach36 · #1 03-02-2008, 01:19 AM

I've had my car for 2 years, valet parked it the other day, and for the first time ever, there was a light on, on the center of the light switch. I didn't even know there was a bulb there, just thought it was a white dot.

Why did it come on, and what is it for?

Thanks,

Jeff 1991 300d, 118k

TylerH860 · #2 03-02-2008, 01:22 AM

Fog lights?

compress ignite · #3 03-02-2008, 02:21 AM

JBACH36,

Turn your main parking lights on (1st click clockwise with the light switch)
then pull the switch out 1/4 inch towards you (Fog lamps are now on).

When you turn the light switch back to Off it "Resets" and turns off the fogs.

pawoSD · #4 03-02-2008, 02:32 AM

From the factory on US-spec cars the light in the switch doesn't work. Its actually intended to come on for the rear fog lamps, which are not present on the US cars. The lenses are empty and have no bulbs/sockets by default. The switch actually pulls out two clicks if you pull enough. That second click activates the rear fogs on a euro, and that little light to let you know they're on.

Jim B. · #5 03-02-2008, 02:44 AM

That is correct, the little light in the center of the switch is for the Euro fogs, but does anyone know WHY the DOT made them illegal, so that the US spec Mercedes Benz cars do not have them?

lutzTD · #6 03-02-2008, 08:21 AM

Quote:

Originally Posted by Jim B.

That is correct, the little light in the center of the switch is for the Euro fogs, but does anyone know WHY the DOT made them illegal, so that the US spec Mercedes Benz cars do not have them?

probably so you wouldnt wreck thinking a car was in your lane coming head on, I think thats why the rear running lights on US cars are red and the fronts are yellow.

pawoSD · #7 03-02-2008, 10:57 AM

Quote:

Originally Posted by lutzTD

probably so you wouldnt wreck thinking a car was in your lane coming head on, I think thats why the rear running lights on US cars are red and the fronts are yellow.

?? The rear euro-fogs on our cars were/are red....

babymog · #8 03-02-2008, 11:56 AM

The first detent is the front fogs, the second detent is front and rear fogs, the rear fog position also turns on the light in the switch.

Rear fogs were not wired nor installed in US cars until '91, your car does have the rear fog, standard starting '91. It is a 21w bulb in the left taillamp only.

markg612 · #9 03-02-2008, 12:53 PM

Quote:

Originally Posted by pawoSD

From the factory on US-spec cars the light in the switch doesn't work. Its actually intended to come on for the rear fog lamps, which are not present on the US cars. The lenses are empty and have no bulbs/sockets by default. The switch actually pulls out two clicks if you pull enough. That second click activates the rear fogs on a euro, and that little light to let you know they're on.

Wrong-
Both my AMERICAN 95's have rear fog lights. They work great! The knob light is active if the rear lights were installed and operational.

hobbitss · #10 03-02-2008, 01:43 PM

Quote:

Originally Posted by markg612

Wrong-
Both my AMERICAN 95's have rear fog lights. They work great! The knob light is active if the rear lights were installed and operational.

Same on my 98....

2.5Turbo · #11 03-02-2008, 05:55 PM

Quote:

Originally Posted by babymog

Rear fogs were not wired nor installed in US cars until '91, your car does have the rear fog, standard starting '91.

Yeah...no rear fogs or working knob light on my '90. I think the bulb for the knob light is there, but it never turns on.

compress ignite · #12 03-02-2008, 06:58 PM

So,would the rear fog light bulb position be the "empty"(no socket) lower
left hand in the rear lens? (on the W124)

aaronkobi · #13 03-02-2008, 07:09 PM

Here's a question about my 300TD... why are there 2 extra notches to the left of "off" on the light switch? I had a 99 SLK that had that feature as well. One click turned only the right parking lights on, the last click turned only left parking lights on... what's that about?

Matt L · #14 03-02-2008, 07:26 PM

Compress,

There is only one rear fog bulb, on the driver's side. The other socket should not even be wired.

Aaron,

The first notch to the right of "off" is the parking lamps. The two notches to the left light just the left side or right side lamps. Apparently, people use these for parking lamps in Europe.

babymog · #15 03-02-2008, 09:11 PM

The left/right park lights will only work with the key off.

In the pre-'91 the rear fog is not wired, nor is there a connector for the lamp. The switch in the US cars also doesn't have the circuit for rear fogs pre-'91 (201 and 124 anyway, I don't know when the other models changed).