If you’re installing an air horn in your car, you’ll need to wire it up properly to get it to work. This guide will show you how to install an air horn relay and wire it correctly so that it sounds when you hit the horn button.
What is an Air Horn Relay?
An air horn relay is a device that allows you to wire your air horn to your car’s existing horn circuit. It’s designed to prevent damage to your car’s electrical system and to ensure that the horn sounds as loudly as possible.
The relay acts as an electrical switch, allowing the current flow to the horn when you press the horn button. When the horn button is released, the relay switches off, preventing the horn from sounding.
The air horn relay also ensures that the horn sounds loudly, even if the battery voltage is low. This is because the relay uses a separate power source to supply the horn with the voltage it needs.
Overall, an air horn relay is a crucial component of any air horn installation. Without it, you risk damaging your car’s electrical system and not being able to sound the horn as loudly as you’d like.
Wiring an Air Horn Relay
To wire an air horn relay, you’ll need a few tools:
| A relay | Wire crimpers | Wire strippers | Electrical tape |
| Zip ties | Fuse holder | Fuse | Ring terminals |
Here’s the step-by-step process for wiring your air horn relay:
Step 1: Disconnect the Battery
Begin by disconnecting the negative terminal of your car’s battery. This will prevent any accidental electrical discharges while you’re working on the wiring.
Step 2: Locate the Horn Wiring
You’ll need to locate the wire that powers your car’s horn. This wire will connect to the air horn relay to activate the horn when you hit the horn button.
You can usually find this wire in your car’s fuse box. Depending on the make and model of your car, it may also be located behind the steering wheel or in the engine compartment.
Step 3: Connect the Horn Wire to the Relay
Using wire strippers, strip the insulation off of the wire that powers your car’s horn. Cut a length of wire long enough to reach the air horn relay, and strip both ends of this wire as well.
Crimp a ring terminal onto one end of the wire that you just stripped. Connect this terminal to the terminal on the air horn relay that is labeled “87”.
Use a zip tie to secure the wire to the other wires in the car to keep it organized and out of the way.
Step 4: Connect the Horn to the Relay
The air horn will need to be connected to the relay in order to sound when you hit the horn button.
Crimp a ring terminal onto one end of a length of wire. Connect this terminal to the terminal on the air horn that is labeled “positive”.
Crimp another ring terminal onto the other end of this wire. Connect this terminal to the terminal on the air horn relay that is labeled “30”.
Step 5: Connect the Relay to the Battery
Crimp another length of wire onto a ring terminal. Connect this terminal to the terminal on the air horn relay that is labeled “87A”.
Crimp another ring terminal onto the other end of this wire. Connect this terminal to the positive terminal of your car’s battery.
Step 6: Install the Fuse Holder
You’ll need to install a fuse holder in order to protect your car’s electrical system from damage. Choose a location near the battery to install the holder, and use wire strippers to strip the insulation off of the power wire.
Insert the power wire into the fuse holder, and connect the other end of the holder to the positive terminal of your car’s battery.
Insert a fuse into the holder. The appropriate fuse size will depend on the wattage of your air horn – consult the manufacturer’s instructions to determine the correct size.
Step 7: Reconnect the Battery
Reconnect the negative terminal of your car’s battery. You’re now ready to test your new air horn!
Frequently Asked Questions (FAQ)
Q: How do I know if my air horn relay is working?
A: If your air horn is sounding when you hit the horn button, then your relay is working correctly.
Q: What size fuse do I need for my air horn?
A: The appropriate fuse size will depend on the wattage of your air horn. Consult the manufacturer’s instructions to determine the correct size.
Q: Can I install an air horn without a relay?
A: It is possible to install an air horn without a relay, but it is not recommended. This is because without a relay, the horn may not sound as loudly as it could, and you risk damaging your car’s electrical system.
Q: How do I troubleshoot my air horn if it’s not working?
A: Check to make sure that the horn is properly connected to the relay, and that the relay is properly connected to the battery. You may also want to check to make sure that the fuse is not blown.
If you still can’t get your air horn to work, consult the manufacturer’s instructions or seek professional assistance.
Q: Is it legal to install an air horn in my car?
A: Laws regarding air horns vary by state and country. Consult your local laws to determine whether it is legal to install an air horn in your car.
Q: How loud is an air horn?
A: The loudness of an air horn will depend on the wattage of the horn. Some air horns can reach up to 150 decibels, which is louder than a jet engine!
Q: How can I make my air horn louder?
A: To make your air horn louder, you can try upgrading to a higher wattage horn, or increasing the diameter of the air horn’s trumpet. You can also try adjusting the horn’s air pressure or installing a larger air tank.
By following these simple steps, you’ll be able to install an air horn relay and wire it correctly for maximum performance. Always consult the manufacturer’s instructions and local laws before installing an air horn in your car.
