Late-124 convenience modules - PeachParts Mercedes-Benz Forum

Jeremy5848 · #1 07-27-2009, 03:11 PM

Did any of the later W124 models ('90-'95 300D 2.5 and E300D and/or gassers) have the window switch feature that allows you to push through the detent and the window will then automatically go all the way down by itself? My '87 does not have that feature; my '96, which is a W210,does. I suspect that retrofitting might be a bigger job than I want to do but was curious anyway.

Jeremy

Oldwolf · #2 07-27-2009, 03:23 PM

My 93 does for both front windows.

Jeremy5848 · #3 07-27-2009, 03:41 PM

Good, thank you. Let me look into the details via EPC.

Does that also allow you to close all of the windows and the sunroof with the remote, as part of locking up the car, or is that yet another "feature" [= future trouble maker] added in later years?

chazola · #4 07-27-2009, 03:53 PM

my '94 does too, and it has the 'total closure' (which still impresses my friends!) from the front door locks... don't have remote system.

compu_85 · #5 07-27-2009, 03:57 PM

If auto down / key in the lock close is an easily retrofittable feature I'd love to have it too....

-Jason

matthias08 · #6 07-27-2009, 04:33 PM

my '95 has is the auto down front windows, I've never looked at the 124 window switch set up, i'd like to figure out how to do it for the rear as well

my sunroof isn't auto open, or close... I have to sit there and hold... which I don't really care for... our 210 & 211 have auto both ways on that too :|

I can open/close windows/sunroof from front door locks, no keyless on my car

Number_Cruncher · #7 07-27-2009, 05:45 PM

My 1995 W124 E300D has the one touch electric windows. If I hold down the button on the infra red remote locking control, the red light continues to flash for a bit, and the electric windows (the front ones at least) and the sunroof close. I've never tried the closure of the rear electric windows.

Jeremy5848 · #8 07-27-2009, 08:04 PM

[after a little research in the 1993 electrical diagrams] The auto-close function in the '93 300D 2.5 and similar models uses a "convenience control module," referred to in the schematics as N57, which lives under the rear seat on the left side. All of the window and sunroof wiring runs through this module, which is part number 202 820 09 26. I haven't priced this part yet but expect it to be very expensive ($ hundreds, at least). A junkyard part would be a better option; at Pick and Pull it would be a "large relay," about $30. I have seen several but didn't know what they were at the time. There is also a "convenience" relay in the fuse/relay box that is part of the circuitry.

The real challenge would be rewiring the electrical system. If one had a late-124 junkyard car from which one could strip parts as needed, and one was taking the interior of the early-124 out anyway (to update to the later style, for example) it would be possible although a lot of work.

It is unlikely that a simple home-made modification would allow this "convenience" function to work in an older W124. This is unfortunate. Perhaps a simpler version could be cobbled together to operate one "most needed" function, the one that you're always forgetting (close the sunroof, maybe?). Let me look at the 1987 schematics.

Jeremy

MBeige · #9 07-27-2009, 09:16 PM

Our 1990 300TE has this feature, both front windows roll down if you push the front window switches all the way through (2 detents). The switch has an extra pin for this function.

The car also has the auto lock/unlock feature when holding the key in the lock/unlock position on the door tumbler, the windows automatically close (lock) and open (unlock) - including the sunroof.

Maybe that's why all access areas (windows/sunroof) go through this convenience module.

Jeremy5848 · #10 07-27-2009, 09:21 PM

Yes, it's like all the exterior lights go through the lamp failure module, all the door switches, etc., go through the alarm, and so forth. Not simple at all.

Bio300TDTdriver · #11 07-27-2009, 10:52 PM

Quote:

Originally Posted by Jeremy5848

[after a little research in the 1993 electrical diagrams] The auto-close function in the '93 300D 2.5 and similar models uses a "convenience control module," referred to in the schematics as N57, which lives under the rear seat on the left side. All of the window and sunroof wiring runs through this module, which is part number 202 820 09 26. I haven't priced this part yet but expect it to be very expensive ($ hundreds, at least). A junkyard part would be a better option; at Pick and Pull it would be a "large relay," about $30. I have seen several but didn't know what they were at the time. There is also a "convenience" relay in the fuse/relay box that is part of the circuitry.

The real challenge would be rewiring the electrical system. If one had a late-124 junkyard car from which one could strip parts as needed, and one was taking the interior of the early-124 out anyway (to update to the later style, for example) it would be possible although a lot of work.

It is unlikely that a simple home-made modification would allow this "convenience" function to work in an older W124. This is unfortunate. Perhaps a simpler version could be cobbled together to operate one "most needed" function, the one that you're always forgetting (close the sunroof, maybe?). Let me look at the 1987 schematics.

Jeremy

You are correct, it is a tad pricey.

Item Number MSRP Core Price Price
2028200926 $448.00 $0.00 $308.20
Electrical - Electrical components - Control module - Comfort
Comfort - Control units 1994 - 1999

pawoSD · #12 07-27-2009, 11:18 PM

My 1990 has this feature as well, it also does the close/open thing with the key from any of the exterior locks. Pretty nifty. I use it to annoy people.

Jeremy5848 · #13 07-28-2009, 01:23 AM

I looked through the early-W124 schematics tonight. Closing the windows would take quite a bit of work and two relay contacts for each window or a total of 8 contacts for the four windows plus a lot of wiring. Not sure I want to go to that much work.

OTOH, the sunroof can be closed (regardless of whether it's slid open or popped up) with only two contact closures, one to provide power for the motor and one to activate the "close" function or the "down" function (one wire does both). That would be easy to do with a relay. Those of us who have retrofitted keyless remote systems to our cars can activate such a relay with one of the extra functions provided with the keyless remote kit. I will post a DIY after figuring out the details. It should also be possible to do the same thing with the key switch in the driver's door but I'll have to do a little more thinking on how to do that without messing up the wiring or setting off the alarm.

Another DIY that I want to write is one that will allow us to turn off the central locking system. I've always wanted to have the option, when I unlock the driver's door to get out, of leaving the other doors locked. That can be done by breaking one wire. It will work whether you're in the car or outside -- unlocking the driver's door will not unlock any of the others.

Thanks to everyone who provided details on the features of the later 124s. I'm jealous.

Jeremy

Oldwolf · #14 07-28-2009, 09:27 AM

I just found out last month that I can keep the key in the locked position on either the front right or left door lock and all the windows and sunroof will close. I thought that was nice because I prefer to drive with windows open.

Now, are you telling me I can hold the key to the left and they all will open automatically?!! That would be way cool.

Jeremy5848 · #15 07-28-2009, 11:47 AM

My '96 will do that with either the key in the lock or the infrared remote. However, that is a W210 and may not be exactly the same as your '93 W124. Try it and let us know.