Horn wiring diagram - PeachParts Mercedes-Benz Forum

psaboic · #1 10-04-2021, 10:44 AM

Does anyone have a wiring diagram for the horns they could post or link to? Specifically for a 1983 300D, but I'm sure it is the same for all W123's.

Thanks

250 Coupe · #2 10-04-2021, 08:59 PM

I think I might have a paper version. I just found 3 of them on the shelf last night.

Michael

250 Coupe · #3 10-04-2021, 09:17 PM

Amazon has the look inside feature for the Haynes manual. Looking at the somewhat blurry image, power comes from fuse 14, goes through the same connector as the combination switch (or one right next to it) then through the horn button. From there, it’s back through the connector then straight to the horns. Fuse 14 looks like it powers the dome lamp also. The horns are grounded to the body somewhere up front. On a W126, I think it’s the 3-4 wires that are bonded to the core support on the passenger side. Corrosion here would cause them to not work.

Michael

250 Coupe · #4 10-05-2021, 12:08 AM

It's split to keep the resolution high but stay under the file size limit.

Michael

psaboic · #5 10-05-2021, 09:41 AM

Many Thanks folks!!! Definitely appreciate it!

psaboic · #6 10-12-2021, 09:30 PM

Quote:

Originally Posted by 250 Coupe

Amazon has the look inside feature for the Haynes manual. Looking at the somewhat blurry image, power comes from fuse 14, goes through the same connector as the combination switch (or one right next to it) then through the horn button. From there, it’s back through the connector then straight to the horns. Fuse 14 looks like it powers the dome lamp also. The horns are grounded to the body somewhere up front. On a W126, I think it’s the 3-4 wires that are bonded to the core support on the passenger side. Corrosion here would cause them to not work.

Michael

Ok, my next (and hopefully final) question is where is the connector that the wires for the horn and the combination switch go thru. I am assuming it is under the drivers side dashboard near the steering column. I'd like to find out if I am getting power to and from the horn switch.....Thanks in advance for any help, and thank you again for the wiring diagram

250 Coupe · #7 10-12-2021, 11:48 PM

I can't find the W123 FSM online, the link at Startek no longer works with the death of flash. I was able to find 54-310 Removal and installation of combination switch which shows a 14 pin plug with 2 rows of 7 pins. It may be at the base of the steering column. It's a very blurry picture, you can make out the plug and some sheet metal structure but there's not enough detail for me to hazard a guess as to where it is.

Michael

psaboic · #8 10-13-2021, 09:57 AM

That is most likely the plug I am looking for as the wiring schematic shows the horn and combination switch wires going into a 14 pin plug. I'll take the trim panel under the steering column off this weekend and see what i can find. Thanks!