speed43

My horns slowly died out completely. I bought oem horns and tested them before installing. Pressed the horn and nothing at all. I can hear the relay click as I press the horn. So I take the relay is good?

I can't find any fuses that say HORN to check if their blown? Ground should be ok since the horns were working before they died right?

cm60k

Did you check the last 5 fuses..?, one of them for Horn, i think it's (15A blue)..

ZAYED,,

speed43

Yes I actually checked all the fuses.

cm60k

If fuse & relay are fine, unplug the wire from Horn, and check if there is a current reach to Horns..!

ZAYED,,

speed43

Ok I will do that tonight. Thanks.

Tony_AMG

Worst case scenario, you'll need to replace the steering angle sensor.

speed43

Tony that has something to do with the horns not working? Why is that? I see that part goes for 258.00 that's expensive. Isn't be able to give a clean to see what happens.

benzslo

if you can hear the relay then it is not your steering sensor aka clock spring.

This is the most basic electric testing. Do you have a digital volt ohm meter? Check power at horn when button is pushed and go from there. Just because the relay clicks, does not mean it is good. Do not assume anything, with simple testing you should have it figured out in 5 minutes.

cm60k

I didn't know steering angle sensor will affect to Horns current..!, is that happened to you before..??

ZAYED,,

cm60k

+10000000000..

ZAYED,,

Tony_AMG

Yes when i got my c43 the horns were not working, i replaced them with new one and same result. checked fuses everything worked. i took a chance by 1st buying the airbag clock spring, but it was not the problem, then i bought the steering angle sensor, which is a separate piece and after installation the horns finally worked.

cm60k

Good info., will keep that in mind..

ZAYED,,

speed43

Ok makes sense. There is no current at the horns when pressing...
It's weird because the horns died one at a time. Last one to go was the passenger side. It sounded like it was in its last "breadth" and than stopped.

Anyone have the electric diagram that may show how the horn wires run. That way I can check for current at each point. I'm also going to replace the relay just in case. Thanks benzslo

cm60k

I have the Horn circuit of 1997/8 C280, i think it's the same of C43 one...!

6151.pdf



ZAYED,,

speed43

Just checked things out.

- There is no power going to the wires to the horn.
- I pulled out the relay and I shaked ita little and I hear something loose?

Dealer wants $35.00 plus tax.
Link below is cheaper and it's the relay that clicks when horn is pressed.

I'm also going to take the relay apart and see maybe I can fix it. But I will buy a new one regardless.

http://www.ecstuning.com/Search/0025420319/ES1615063/

speed43

Thanks zayed! I saved this.
Btw zayed I could not find a fuse that says horn. Are you sure there is a fuse for the horn?

cm60k

Yeah, when i had problem with Horns, i think i replaced the blue fuse(15A) #41, front of black relay..



ZAYED,,

speed43

Ok cool, I will pull it and see. Thanks.

speed43

Btw, when I pulled off the relay that clicks when pushing horn. The window washer pump stopped working. This relay is the green one in zayeds picture, does this green relay SHARE horn with washer fluid pump? And if yes than this relay should be good right since when off washer fluid pump stops working and when in it starts working?

Is this green relay the one for the horn? I searched for c43 and horn relay and it comes out color black like the one in zayed picture next to the yellow relays.

cm60k

Yeah mate,

Horn relay should be the black one #: "002 542 11 19",



maybe the green one has bypass connection or something, not sure..!

ZAYED,,

Tony_AMG

http://www.mbpartsworld.com/showAsse...roduct=7597403
Check this link. has a bunch of relays and descriptions. Helps me alot

speed43

Nice find. Thank you!

speed43

Well the horns finally work. The problem was the black horn relay.
Although it clicked when the horn was pressed it was still bad (just like Benzslo said).

And with the tips I got from everyone I learned a lot and got some nice links which are saved for reference. Thanks everyone for your help in solving this!