View Full Version : Horn troubleshooting

02-16-2010, 01:57 PM
Trying to get the horns to work on my Spit proj. New relay only clicks. Circuit continuity thru to the horns, power okay, horns test okay. Any thoughts?
Thanks, Don '71 Spitfire '65 TR4 Missoula, MT

02-16-2010, 02:16 PM
When you say the horns test OK are you saying they sound when you apply 12 volts ?

02-16-2010, 02:51 PM
If the horns work when you apply 12 volts as Jim suggested and you have checked everything else, make sure the black wires are connected to a good ground. I believe they either go back to the steering rack or in some years to the radiator support.

02-16-2010, 03:01 PM
I would check to see if when the "relay clicks" it is actually switching +12v. Get a VOM and see if you get the 12v when the horn button is depressed. If you do, then as others have suggested, check to make sure you have a good ground.

02-17-2010, 08:27 PM
Just to expand on that a bit, do your voltage tests with the horns connected. A connection with too much resistance to actually power the horns can still show "continuity".

02-18-2010, 07:09 PM
Great points from all. Horns were tested w/ 12v, will check the ground. The resistance aspect may be my nemesis. Appreciate all the ideas, and will advise when I get back to it.

Thanks, Don L

02-18-2010, 07:20 PM
I would take a 12 volt lead and energize the the horn lead at the relay to confirm that portion of the circuit.