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Gerry M
06-17-2014, 07:46 PM
When I push horn button the relay clicks but the horn does not beep. So I have power to the relay right?
I have attached some sketches. The existing wiring is shown. The Advance Auto-Wire diagram shows a different wiring arrangement. I have tried rewiring according to Advance and same result. Relay clicks but horn does not beep. I can get the horn to beep with purple-yellow wire on C1 and main purple wire on W1 and when I touch the second purple wire to C1 the horn beeps. So I am thinking horn is OK and horn push button is OK and problem is at the relay.

QUESTIONS: Am I correct - the problem at the relay? Is the problem an incorrectly wired relay? Is the problem a faulty relay? Other?

33594

DNK
06-18-2014, 02:54 PM
Relays are cheap. Try a new one.Are you sure your grounds are working?

Keoke
06-18-2014, 03:23 PM
Check on line for a shematic of the relay and see if that relay is normally open or normally closed it sound like you have a normally cloesd one????
a
This one is normally open
.
Wire it as follows"& assumes Neg Gnd.

85 is Pwr from horn button
86 Is Gnd
30 is +12V Pwr
87 is switched +12v power to hornhttps://static.grainger.com/rp/s/is/image/Grainger/5ZMU4_AS01?hei=800&wid=935

kbatl
06-20-2014, 03:43 PM
When I push horn button the relay clicks but the horn does not beep. So I have power to the relay right?
I have attached some sketches. The existing wiring is shown. The Advance Auto-Wire diagram shows a different wiring arrangement. I have tried rewiring according to Advance and same result. Relay clicks but horn does not beep. I can get the horn to beep with purple-yellow wire on C1 and main purple wire on W1 and when I touch the second purple wire to C1 the horn beeps. So I am thinking horn is OK and horn push button is OK and problem is at the relay.

QUESTIONS: Am I correct - the problem at the relay? Is the problem an incorrectly wired relay? Is the problem a faulty relay? Other?

33594

Mine did the same thing. I pulled the horns off and applied power direct to them. One sounded like it was seized and wouldn't honk and the other sounded like a cow on it's last breath. Sprayed some penetrating oil into the horn and one sounded better and started to work but the other was still dead. Also, check power at the horn to see if you are getting full voltage. Some of the bullet connections around the horn area are prone to corrosion and falling apart.

Rather than go with the original sound, I think I may find some higher frequency European sounding air horns.

Kevin

TR3driver
06-20-2014, 06:06 PM
Gerry, did you get your horns working? I'm a bit late to the party, but I believe you are correct. Since jumpering across the contacts makes the horn work; and you can hear the relay click; the most likely explanation is a bad horn relay.

Horns are funny loads, very inductive and with very high peak current (relative to the average current measured by a meter). You might want to replace with a purpose-made horn relay rather than a general purpose one.

The two wiring diagrams you show are equivalent, there is effectively no difference between the W1 and W2 terminals and the only difference in the diagrams is the way that W1 and W2 are connected.

PS, that is a single pole, single throw, normally open relay. If you use a common SPDT replacement, just don't connect the normally closed (87a) contact. In case you are interested, there is a nice write-up on relay operation (showing a horn circuit basically identical to yours) at https://www.autoshop101.com/forms/hweb2.pdf