Horn Troubleshooting on suzki samurai

Due to the age of the vehicle, it could be that you aren't getting a good ground for the horn to work, you may need to clean the mount areas to ensure a good contact. I suggest that you first test for voltage at the horn, you should get 12Volts on the positive side when energized. Once you know that 12Volts are reaching the horn, it's either the horn that is bad, or the ground contact. If no voltage, then you need to check the relay. It's not a bad idea to just test the horn itself. The last resort is the steering wheel horn connection if all else fails.

There are several places that you could start, but I would check the fuse first. If it is good and there is 12V to the fuse I would then check the horn button under the air bag and make sure that there is voltage there. You can then check to make sure that if you pass 12V across the switch that the horn sounds. If not check to make sure that the horn is getting the 12V when the horn switch is made. If you are getting 12V at the horn but it isn't sounding, replace the horn. Just make sure to be careful working around the air bag. If you do not know what you are doing, find a competent mechanic.

There are several ways of wiring a horn and you need to understand the circuit your car uses - a circuit that uses a central steering wheel button that doesn't use a relay, usually has a two terminal horn with a supply from the fusebox to one horn terminal and the other terminal wired to the steering wheel button, which when pressed grounds the earthy side of the horn to the steering column.
When a relay is added to that circuit, one or more horns can be used that are either single terminal or two terminal types.

A single terminal horn has an internal ground and a two terminal type needs one terminal grounding...

The horn is usually located in front of the radiator/condenser. I would test it by applying 12volts, if it works you know it is the horn relay or the horn button itself.

The elements to a horn circuit in your vehicle are:

1. Steering wheel horn button;
2. Actuator wire in steering column;
3. Ground wire for steering column;
4. Horn relay; and
5. Horn.

Start troubleshooting!

I go through many different steps in troubleshooting the horn on a 2004 Toyota Sienna on this webpage: John Fixes Stuff Horn Won Work How to Troubleshoot The Horn on 2004 2010...

Check the plug to the hor, then the fuse/relay, then the steering wheel switch.

The most common cause is that the ribbon contact drum under the steering wheel is faulty and has a broken filament. The part is called the "clock spring contact drum"

check the fuse.I think they are on the same fuse/

For starters, check the fuse block and inspect the most related fuses, like HORN, ACC, dashboard. The owner's manual should have a troubleshooting guide for the most basic stuff, including the horn. Try this for now and see how it works. Let me know if the problem persists. Good Luck.