Greetings, upon replacing a defective passenger window switch, I'm confronted with two mystery wires, one gray, one black, that join, then plug into some red plastic gizmo between the front & rear switches. How do I transfer this to the new switch without damaging it, & what does it do?
Thanks in advance!

Ok a few questions first

Is this a 123 or 124 chassis (what year is your car?)
Is this the main switch in the console up front, or one of the back door local switches?

__________________
The OM 642/722.9 powered family
Still going strong
2014 ML350 Bluetec (wife's DD)
2013 E350 Bluetec (my DD)

both my kids cars went to junkyard in 2023
2008 ML320 CDI (Older son’s DD) fatal transmission failure, water soaked/fried rear SAM, numerous other issues, just too far gone to save (165k miles)
2008 E320 Bluetec (Younger son's DD) injector failed open and diluted oil with diesel, spun main bearings (240k miles)

1998 E300DT sold to TimFreeh
1987 300TD sold to vstech

1985 W123; front switches located in the console

The hazard flasher switch is red but there is another switch for the speakers that is a roller switch.

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84 300D, 82 Volvo 244Gl Diesel

Thanks D911, that stuff's all working, these wires are still attached to the dead window switch, & I don't want to break whatever the red plastic thing is getting it out, nor do I really want to cut the wires, especially until I find out what they do...

On a 123 the child safety switch is between the drivers and left rear window switch.

Note that the left and right switches are different. The left switch has the child lockout and the right switch does not. Be sure you are not trying to put a left switch on the right side as they are wired differently.

That 2 pin plug is probably for the child lockout switch.

The child switch interrupts the ground path to the rear window switches to prevent them from being operated. But only from the back. They did arrange it so that the front switches still worked. Pretty clever.

__________________
The OM 642/722.9 powered family
Still going strong
2014 ML350 Bluetec (wife's DD)
2013 E350 Bluetec (my DD)

both my kids cars went to junkyard in 2023
2008 ML320 CDI (Older son’s DD) fatal transmission failure, water soaked/fried rear SAM, numerous other issues, just too far gone to save (165k miles)
2008 E320 Bluetec (Younger son's DD) injector failed open and diluted oil with diesel, spun main bearings (240k miles)

1998 E300DT sold to TimFreeh
1987 300TD sold to vstech

Thanks jay_bob; looking at an intact switch panel in a working car, what is the function of the space between front & rear rockers in the passenger side switch? This would be in the exact same place as the child lock-out switch in the driver side switch? That is to say, directly opposite the CL-O switch? Could it be a light that indicates the switch is on? That possibility came out of thin air just now...

No the passenger side switch just has a filler piece, nothing electrical there between the switches.

__________________
The OM 642/722.9 powered family
Still going strong
2014 ML350 Bluetec (wife's DD)
2013 E350 Bluetec (my DD)

both my kids cars went to junkyard in 2023
2008 ML320 CDI (Older son’s DD) fatal transmission failure, water soaked/fried rear SAM, numerous other issues, just too far gone to save (165k miles)
2008 E320 Bluetec (Younger son's DD) injector failed open and diluted oil with diesel, spun main bearings (240k miles)

1998 E300DT sold to TimFreeh
1987 300TD sold to vstech

Aftermarket window switches for the W123 often lack the internal light that the original Mercedes switches have.

Thanks BWhitmore, I’m gonna run with that. There’s a hole in the square plastic piece that went between the two rockers on the original switch plate, & I’m figuring the red plastic gizmo was the light. Cheers everybody!