I recently found a 75 Bonneville that of course needs some work. A good starting point would be a simply fixing the horn.  Finding the Horn relay is proving to be a tough challenge does any one know where it is located?

welcome jim 

try rockauto 

or ames 

but cheapest is to  use a generic relay that you can hide away 

we love pictures around here ..... would love to see your 75 

Sorry my post was misleading, I ment where on the car is the relay located.  Ill try to get some pics up later.

Bet it’s on the fire wall or  drivers side inner fender 

JustA follow the wires back from the horns 

Edited December 20, 20241 yr by 64 kiwi boni

Yes, follow the wires.  On my 70, its almost out of sight on the driver's side firewall under the inner fender as Chris mentioned.  With four wires to it if I remember correctly but my car is a convertible so that may add an extra wire.

Rick

I will let you know what I find . Thank you for your suggestions.

Could the relay in the center of the picture attached to the fire wall be the one?  It has a green wire under the screw that holds it in place and 3 other wires in the relay itself.

That could be it but does its wire colors match the colors on a 1975 Bonneville wiring diagram?

Hey Jim - I just looked up a picture of a 75 Bonneville.  That's a nice looking car. 

Rick

Thank you and you are right, its the blower relay. back to looking

13 hours ago, B52bombardier1 said:

That could be it but does its wire colors match the colors on a 1975 Bonneville wiring diagram?

Hey Jim - I just looked up a picture of a 75 Bonneville.  That's a nice looking car. 

Rick

DO you have the wire colors on the diagram? I traced the wires from the horns back through to the firewall. They are in a plastic loom (along with the headlight wiring) from the front end all the way through the lower part of the fire wall. No breaks in the loom under the hood. Once they get inside the car It goes up under the dash and I cant see them any more. There is one relay in the kick panel that has three wires in it but they look too large for just the horn. I m out of places to look.

That horn relay carries some very heavy current and will have thick wiring.  The Haynes manual for 1975 indicates a 10-gauge red wire, a 16-gauge black wire and a 20-gauge black wire with a pink stripe.   

Rick

Never found the horn relay. Wondering if it wasnt part of the seat belt ignition interlock this car had. It has no key in ignition or seat belt buzzer either. Any thoughts?