i changed out my oil/fuel/temp gauge the other day and now my horn will no longer work. all other functions work: lights, gauges, wipers, brights, buzzers, everything works. it's just the horn.

is there any way the cluster itself might hold the answer? there's no ice cube relay on the back that has anything to do with the horn, correct?

the wiring coming out of the steering column is in two parts. the first wire runs to the huge switch and plugs in near the front of the kick panel. it's long and runs perpendicular to the wheel. the other wire is smaller and ends at a plug that looks identical to headlight plugs with blue, yellow, white, green, and red wires. that plug seems a bit loose but no amount of fiddling with it changes things. does anyone know which has to do with the horn?

i've got a wiring diagram but i have absolutely no idea what i'm looking at. wiring is my biggest mechanical weakness.

the horn worked perfectly, i changed the cluster, it no longer worked. i'm completely at a loss?

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1985 300D - 1984 Euro 280E AMG Clone (SOLD) - 1978 280CE (SOLD) - 1983 300D (SOLD) - 1981 300D (SOLD)

Use your finger.

Have you checked the fuse?

Charlie

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

yes, forgot to mention that i did take a look at the fuse. eyeballed it, looked fine, replaced it with the spare that sits in the box just in case, and that didn't do the trick either.

using the finger works well for some applications but moms don't seem to like it when i use it to get their kids out of the road...

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1985 300D - 1984 Euro 280E AMG Clone (SOLD) - 1978 280CE (SOLD) - 1983 300D (SOLD) - 1981 300D (SOLD)

If you're looking at the FSM schematic for the '78 280CE, it's not helping you. The components are mis-marked. Power comes out of fuse 14, then goes to number 18, only number 18 in the picture should really be 19. There are two 18's in the pic - not just two horns that are both 18 - if you look up about 1/2 inch in the diagram you'll see the real 18 that's a door switch. The horns should be marked 19 and go to number 35 and that's the horn switch.

The horns should be off the 14-pin connector that's shared with turn signals, high beams, wipers, etc. Since you say those work, that connector should be okay.

The horn wire is supposed to be black/pink/yellow and the brown wire next to it is the path to ground, sockets 4 and 5. Inspect those wires and connections. Plug the connector back in and see what happens.

If no luck, post back with what you see and what you've done. I presume you didn't do anything like remove the steering wheel to remove the cluster, or remove the combination switch.

If so, then maybe the carbon brushes in the combo switch.

thank you!!! i tossed that thing aside when i ran into this. it was bad enough looking at that thing to then realize there was no 19...

found a new one for about $50, should i just replace it?

just take a look, shoot some compressed air at them, and re-connect?

no switches or steering wheels were removed during this operation.

are those replaceable on their own or do i just buy a new switch?

i'll get at this job today after work and report back, thanks!!!

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1985 300D - 1984 Euro 280E AMG Clone (SOLD) - 1978 280CE (SOLD) - 1983 300D (SOLD) - 1981 300D (SOLD)

well, scientific reasoning took over and i... jiggled all the wires and plugs. now my horn works great...

i guess i'll be getting a new switch in the future. thanks for the help!

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1985 300D - 1984 Euro 280E AMG Clone (SOLD) - 1978 280CE (SOLD) - 1983 300D (SOLD) - 1981 300D (SOLD)