News: Putting FUN and FRIENDLINESS, FIRST into owning and learning about AMC small bodied cars, primarily Eagles, Spirits and Concords as well as vehicles built in AMC's Mexican subsidiary, VAM.

The AMC Eaglepedia can now be accessed using the buttons found below  This is a comprehensive ever growing archive of information, tips, diagrams, manuals, etc. for the AMC Eagle and other small bodied AMC cars. 

Also a button is now available for our Face Book Group page.


Welcome to the AMC Eagles Nest.  A new site under "old" management -- so welcome to your new home for everything related to AMC Eagles, Spirits and Concords along with opportunities to interact with other AMC'ers.  This site will soon be evolving to look different than it has and we will be incorporating new features we hope you will find useful, entertaining and expand your AMC horizons.

You can now promote your topics at your favorite social media site by clicking on the appropriate icon (top upper right of the page) while viewing the topic you wish to promote.


  • October 04, 2024, 10:50:30 PM

Login with username, password and session length

Author Topic: Horn not working - diagnosis?  (Read 1191 times)

0 Members and 1 Guest are viewing this topic.

Offline 86Woodgrain

  • Administrator
  • Eagle
  • ******
  • Posts: 138
  • Thumbs Up 8
Horn not working - diagnosis?
« on: December 20, 2022, 02:22:41 PM »
My horn does not work. I checked for 12V at the horn connector and it does not get power when the horn button is pressed.

HOWEVER, I checked for continuity at the same connector and it seems to have continuity against the negative and POSITIVE battery terminal. That doesn't make sense to me.

Am I losing my mind? How can the horn wire connector have continuity to power when no one is touching the horn button?

I have read that there is a horn relay so I am going to investigate that next.

Edit: Hmmm and I just realized I can jump 12V directly to the horn to test it.
« Last Edit: December 20, 2022, 02:23:30 PM by 86Woodgrain »

Offline MIPS

  • Eagle Limited
  • *****
  • Posts: 519
  • Thumbs Up 50
Re: Horn not working - diagnosis?
« Reply #1 on: December 20, 2022, 03:18:31 PM »
The horn button goes through the horn relay (because the horn draws several amps and will burn the horn button out) which I *think* lives next to the starter solenoid. Even with the horn unplugged you should hear it click when the button is pressed. It just connects and disconnects always-on battery voltage but I forget if that or horn B+ and the control side are fused.
You can test the horn by putting it directly across the battery.
« Last Edit: December 20, 2022, 03:24:15 PM by MIPS »

Offline Illeagle1984

  • Manic Mechanic
  • Premium Member
  • Eagle
  • *****
  • Posts: 112
  • Thumbs Up 14
Re: Horn not working - diagnosis?
« Reply #2 on: December 21, 2022, 06:59:39 PM »
The horn relay is indeed on the passenger firewall.  It's a three wire thing.  There's a pink wire which should be hot all the time, which supplies power to both sides of the relay, the switch and the load (most relays are 4 wire).  The gray wire goes to the horn button; when it is grounded, the horn relay turns on and supplies power to that black wire.  The horns have a case ground.  So you have a procedure:

- Ground the gray wire, bypassing the button.  If the relay is bad, you can...
- Put power to the black wire.  If the horns still don't sound...
- Put a jumper cable with power directly on the horn terminal.

If it still doesn't sound, the horn is bad, or the ground is bad. :)
It's getting crowded down here:
1973 Ford Mustang "Rustang"
1984 AMC Eagle Sedan "IllEagle" 183k
1984 AMC Eagle Wagon "Eagle 2"
1996 Cadillac Eldorado 178k
1998 Oldsmobile Eighty-Eight 239k
2002 Cadillac Eldorado Doral Edition
2005 Chevrolet Silverado 1500 179k

 

SMF spam blocked by CleanTalk