The relay center should be in hte engine compartment. Once you open the hood and are facing the front of the car look to the back left by the hood hinge. You should see a black box that has a diagram on it. Take the cover off and use the diagram on the cover to pinpoint which relay is the horn. Hope that helps.
Yes, there's a fuse + relay box in the engine bay, but that's not where the horn relay is.
Horn relay is on the under-dash fuse panel. Left (driver's side, in the USA) side of car. Horn relay is way up at upper edge of the panel, mounted on a tab so it's sort of off the edge of the panel. Relay has a gray housing with a 4-wire connector going to it. Squeeze tab on the connector lets you pull it off the relay. Squeeze tab at base of relay lets you pull it off the panel base.
Reference:
http://www.Honda-tech.com/showthread.php?t=2153943
How do you repair 1999 Honda Civic Horn?
The horn relay is mounted underneath the dashboard on the 1995 Honda Civic. The unit is mounted on the upper right of the cabin fuse box.
On the Steering...
The 1997 Honda Civic Horn relay is found under the drive side dash panel. The relay is mounted next to the starter relay on the right side of the fuse box.
http://wiki.answers.com/Q/Where_is_the_horn_relay_on_a_1995_Honda_Civic"
Near the engine (inside the bonnet)
More than likely a blown fuse or defective horn relay.
The relay just plugs into the fuse/relay box, installing it means reading the owners manual to determine the correct location and plugging it in.
First thing to check is the fuse. If the fuse is good check the relay. If that is good check wiring. Can also be the horn switch or the horn itself.
The 1991 Honda Accord horn relay switch can be found mounted to the radiator. The horn relay switch will be on the right hand side of the radiator housing.
not having a horn
red