Remove the plastic "filler panel" between the radiator mount (top) and the front grill on the driver side. They are attached to the radiator mount (top)and are not visible unless the "panel" has been removed.
In the trunk, remove the back panel by unscrewing the four plastic knobs on the roof of the trunk, there is the entire fuse box for the vehicle
Carefully
where is the horns for 1978 cadillac
Under the battery tray
under the fuses beneath the hood. look back and it has a cover on it that you have to remove. then 2 fuse boxes. relays are beneath there. horn relay should be on far right.
Horns (there are usually 2 or 3) are located in the top forward fender area. Accessed from under the hood, you will find them outboard of the windshield washer fluid jug on the drivers side or outboard of the battery on the passengers side. Cadillac Man
To replace the horn on a 1999 Cadillac DeVille Concours, first, disconnect the negative battery terminal to ensure safety. Remove the engine cover if necessary, then locate the horn, which is typically mounted behind the front grille or in the engine compartment. Disconnect the wiring harness from the horn and unbolt it from its mount. Install the new horn by reversing the steps, ensuring all connections are secure before reconnecting the battery.
In a 1977 Cadillac, the horn is typically located behind the front grille, mounted on the front of the vehicle. It is usually connected to the steering wheel via a wire harness, allowing the driver to activate it by pressing down on the horn ring or center of the steering wheel. Some models may have more than one horn for a richer sound. If you're having trouble finding it, consulting the vehicle's service manual can provide specific guidance.
on the middle of the steering wheel
If you mean the warning light, This is done with a scan tool with the appropriate program. It should be noted however, that the light will turn on again if the problem is not located and fixed. If the horn also doesn't work as well as the cruise control, my money would be on a bad clockspring. The clockspring located in the steering column provides ground for the airbag,horn and cruise control.
In a 2000 Cadillac Seville, the horn is typically located behind the front grille, near the front bumper. It is mounted on the driver's side of the vehicle. Accessing it may require removing the grille or other components for maintenance or replacement.
in gloves box