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Discussion Starter #1 (Edited)
ok guys so i searched but to no avail so i turn to u for help!!

I had a similar issue a few years ago. Basically the background is my 2001 horn (at the time 3yrs ago) was only half functional and made a muffled tone compared to full on blaring horn that I was used to. After some diagnosis at the time I ended up replacing one of my horns (forgot which either hi or low) and the problem resolved. My horn was functional for the last few years with NO problems whatsoever

In the last month or so my horn reverted back to a muffled sound which indicated to me that either the hi or low horn was faulty. I thought it was the same issue and ordered a set of horns (BOTH hi and low) from another is300er to solve the problem. In waiting for the set of 2 horns to arrive I tried using my horn one day and NO SOUND came out at all this time. I don't know if I overuse the horn or what but it went out and thats when I realized how many situations actually require the use/or potential use of a horn. It became a safety issue that I had to address and I eagerly waited for the replacement set of horns to arrive.

After they showed up, lazy me, I took another 3 weeks to install them. on a whim I decided to check the horn FUSE and low and behold it was blown. I replaced it and got the function back of a muffled horn (meaning one of the horns worked and the other still didn't as before). After a quick diagnosis I realized it was my PASSENGER SIDE horn (don't know if this is considered 'hi' or 'low') was faulty. I went to replace the horn and it still doesn't work, SO BUMMED!!!

So I decide, again on a whim, to test the factory alarm by pushing the panic button. the alarm sounds full blast and sounds perfect like I was blaring the regular horn with no problems. The passenger side horn still DIDN'T work, the drivers side DID work, and the drivers side horn near the windshield worked just fine. I don't know what wrong here. The passenger side horn is non functional for some reason but when the alarm is set off using the panic button everything sounds normal. I didn't even know that the horn by the drivers side windshield went off with the alarm until I rested it today.

ANYONE HAVE ANY IDEAS??? I can only presume I have a problem with the wiring for the horn on the passenger side but I am not really sure. A few other notes of what I tried...

1. installing new horn on passenger side
result: STILL no sound on passenger side

2. switching working drivers side horn to passenger side
result: no sound on passenger side (and obviously no sound on drivers side since used from the drivers side)

3. installed new horn on drivers side, nothing on passenger side
result: very WEIRD. The drivers side had no sound and when I hit the horn I could hear a 'click' noise that sounded like a relay trying to send power to the horn but no luck. I would have expected the horn to still work since all I did was swap out a working horn on the drivers side for another (presumed) working horn.
Personal conclusion: even the new horn I bought for the drivers side was defective??

4. Reinstalled original drivers side horn on drivers side
result: working horn on drivers side only

5. Is there any way I could get the working drivers side horn to work with the drivers side horn near the windshield when I honk my horn for a 'normal OEM' sound???

PLEASE HELP or any suggestions would be GREATLY appreciated, I am at a loss for what to do or what it could be. IN my mind either the horn wiring leading to the passenger side is faulty or.... am I missing something here??? Is there another fuse or something for the passenger side horn although I think there is only one wire that connects both. I have preowned replacement parts so could it be both horns are non-functional?? Any other ideas? Thanks again!!
 

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it sounds like you have a bad/corroded connection to the horn or you have a bad ground (mounting) for the passenger side horn. both horns are fed from one fuse, go thrue the steering wheel switch to energize the relay and then that one positive wire goes in parallel to each horn. the relay would not be the culprit as you do have at least one horn that works. one positive wire is fed to each horn and the negative is the mounting bolt that grounds the horn to the car. to verify if its a wiring or grounding problem, disconnect the horn plugs use a meter and have a friend hold in the steering wheel switch and test that one wire that goes to each horn to a known good ground to see if you have +12vdc at each plug(each horn). if you do have +12vdc to ground, that would rule out a wiring issue or relay(which I bet you do have +12). if you dont have a meter, have a friend push the steering wheel switch and jiggle the connection to the passenger horn or the horns mounting(use ear plugs). its a very simple circuit. i would clean the mounting area where the passenger horn mounts to the chassis to insure a good ground. a bad ground or loose/corroded connection(the plug) would cause excessive current and would cause your fuse to blow. below is a generic diagram w/o the relay on how it is wired. basically clean the area where the passenger horn mounts to and make sure the wire that goes from the driverside horn to the passenger side horn is intact.

BTW...in your #5 comment, the device you said located near the windshield is not part of the actual steering wheel horn system. it is a piezo horn, the black round disc, which simply beeps for the alarm activate/deactivate and is part of the alarm system
 

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Discussion Starter #4
it sounds like you have a bad/corroded connection to the horn or you have a bad ground (mounting) for the passenger side horn. both horns are fed from one fuse, go thrue the steering wheel switch, and then that one positive wire goes in parallel to each horn. i'll have to double check but i dont think there is a relay for the horns(either way, the relay would not be the culprit as you do have at least one horn that works). one positive wire is fed to each horn and the negative is the mounting bolt that grounds the horn to the car. to verify if its a wiring or grounding problem, disconnect the horn plugs use a meter and have a friend hold in the steering wheel switch and test that one wire that goes to each horn to a known good ground to see if you have +12vdc at each plug(each horn). if you do have +12vdc to ground, that would rule out a wiring issue. if you dont have a meter, have a friend push the steering wheel switch and jiggle the connection to the passenger horn or the horns mounting(use ear plugs). its a very simple circuit. i would clean the mounting area where the passenger horn mounts to the chassis to insure a good ground. a bad ground or loose/corroded connection(the plug) would cause excessive current and would cause your fuse to blow. below is a generic diagram on how it is wired, as for the relay ill double check but i dont think there is one for this application. basically clean the area where the passenger horn mounts to and make sure the wire that goes from the driverside horn to the passenger side horn is intact.

BTW...in your #5 comment, the device you said located near the windsheild is not part of the actual steering wheel horn system. it is a piezo horn, the black round disc, which simply beeps for the alarm activate/deactivate and is part of the alarm system
wow Dude all I can say is thanks for taking the TIME and energy to post a lengthy detailed reply and especially the drawing!!!

I am a blonde now that I look at ur drawing I can see where I have faltered (I think). Each time I tested the new horns I never screwed them back on the car (not knowing they had to be GROUNDED to work!!). All my above scenarios make Perfect Sense now that I look back as to why they did or didnt work. I will wait for the AM and some warmth to open my grile back up but I'm sure after I install them "mounted" on the car instead of just plugging the new horns in they will work. I will keep u posted. Much appreciated again for ur feedback sir!!!

PS: looks like simple things get me every time.... :)
 

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In the 4 years I have owned my car...I dont recall hitting the horn more than once.
Most if not every car inspection requires the horn to work. Every time I have taken my car to different places they DO test the horn for it to pass. It can be considered a safety device...even tho I can't remember the last time I used mine either.
 

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EDIT: there is a horn relay located under the hood by the battery...that relay box and inside its located near the EFI relay. Just wanted to add this but I doubt its related to the OP issue
 

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Discussion Starter #9
Much thanks again Jason!!! Horn worked like a charm after I had it grounded properly with the install. The old bolt was a BiTc# to get off and I ended up tearing a quarter sized chunk of metal off but I did drill another hole nearby to resolve the issue. Your picture again is what got me to see the BIG PICTURE of what i was doing wrong.

Much thanks again, I went to give u repp but .net says I have to.... "You must spread some Reputation around before giving it to jasonm4444 again."

Hope this helps others too :)
 

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No problem buddy...glad you got em working. Ill have to edit my drawing on a PC to show that the steering wheel energizes the horn relay which closes the contacts to send power to the horns. (so all the circuit is there)
 

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Thanks for posting a very informative thread! I've been wondering about the numbers. In the year I've been here, I recall at least 3 or 4 more folks that are no longer on here. Welcome & keep up the great work!
 
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