Is your stock car horn sounding weak? Installing an aftermarket horn can provide louder, more personalized sounds to grab attention on the road. With some wiring knowledge and mechanical skills, this useful upgrade is doable for the average DIYer.
Let’s run through key steps to safely remove your old horn and install a new eye-catching or ear-catching replacement. Custom horns come in all kinds of crazy sounds these days.
Table of Contents
- Getting Prepared
- Removing the Factory Horn
- Installing the New Horn
- Troubleshooting Installation Issues
- Installation Best Practices
- Legal Considerations
- When to Call a Pro
Like any car modification project, advance preparation sets you up for success when installing your new horn:
1. Pick Your Horn Sound
Browse the many horn sounds available online or in auto parts stores. Consider volume, tone, uniqueness, and number of trumpets needed. Measure your available grill space to size properly.
2. Gather Tools
You’ll need common hand tools like wrenches, pliers, screwdrivers and trim panel tools, plus a test light and electrical tape. Ensure you can access the horn’s mounting location under the hood.
3. Review Wiring Diagrams
Consult a vehicle-specific wiring diagram to understand the horn’s electrical hookup in your model. This lets you plan the wiring adaption needed.
4. Safety First
Disconnect the battery before beginning to avoid electrical shorts and airbag deployment. Work safely with proper precautions.
With details covered, you’re ready to give that old horn an auditory upgrade!
Removing the Factory Horn
The first stage is safely removing your existing horn assembly:
1. Access the Horn
Locate the horn behind the front grille area. Remove any fasteners or trim components obstructing access. Avoid damaging brackets or radar sensors during removal.
2. Disconnect the Wiring
Unplug the electrical connector leading to the horn. If it’s not accessible, trace wires back and snip them a few inches away to create slack.
3. Remove Mounting Hardware
Remove any bolts or brackets securing the horn. Carefully detach it without damaging threads or mounting locations.
4. Transfer Any Brackets
If the new horn requires existing brackets, transfer them over now. Note any rubber grommets or isolators to replace during installation.
Work methodically to remove factory parts without causing collateral damage.
Installing the New Horn
With the old horn removed, it’s time to adapt and mount its replacement:
1. Check Fitment
Test fit the new horn to ensure it aligns with mounting holes and avoids interference with other components under the hood.
2. Install Mounting Hardware
Use original bolts and brackets if transferring over, or self-tapping screws and washers to mount the new horn securely. Don’t overtighten.
3. Wire the New Horn
Extend the original connector using suitable gauge automotive wire, or replace with new wiring and terminals. Verify polarity – horns are typically polarized.
4. Secure Wiring
Keep wiring away from hot or moving components using wire loom. Seal connections thoroughly with heat shrink tubing or tape.
5. Test Operation
Reconnect battery power when clear of hazards. Press the horn button briefly to confirm proper operation before finalizing installation.
With the horn mounted and wired, it’s ready to annoy anyone nearby very soon!
Troubleshooting Installation Issues
If your new horn fails to operate properly, work through these troubleshooting tips:
- Check for loose wiring connections, frayed wires or reversed polarity.
- Inspect all fuses related to the horn circuit. Replace any damaged ones.
- Test the horn button signal using a voltmeter. If no signal, trace wiring for breaks.
- Measure voltage directly at the horn terminals during activation. If voltage drops below 10V, insufficient current is present.
- Isolate the horn from brackets to verify vibration dampening is not interfering with sound.
- Ensure the horn is compatible with your vehicle’s electrical system voltage.
- Try adjusting the horn’s direction facing to project sound optimally.
Methodically verifying electrical continuity and integrity resolves most new horn installation difficulties.
Installation Best Practices
Adhering to smart installation techniques ensures your new horn functions great for years:
- Point the horn down slightly to avoid water intrusion into trumpets.
- Apply weatherproof dielectric grease on terminals to prevent corrosion.
- Wrap wiring with protective loom and grommets at pass-through points.
- Follow vehicle-specific mounting guidelines for ideal positioning.
- Confirm the horn is compatible with high pressure vehicle washing.
- Routinely inspect wiring condition and horn brackets.
- Turn off the radio to better align directional or tonal horns.
Proper planning prevents poor performance! Take the time to do it right.
While customized horns allow great self-expression, beware of these potential legal pitfalls:
- Many areas prohibit overly loud horns audible from over 200 feet away. Research local noise ordinances.
- Horns resembling emergency vehicle sirens are often restricted or outright illegal on civilian vehicles.
- Using horns expressively may violate laws against improper signaling or nuisance noise. Avoid overuse.
- Mounting horns behind grilles is recommended—exposed under hood mounting may exceed maximum vehicle projection limits.
It’s wise to research your local regulations thoroughly so your creative horn doesn’t lead to citations. And of course, avoid rude or offensive sounds, no matter how funny.
When to Call a Pro
Installing your own custom horn can be very rewarding, but consider letting a professional handle it in these cases:
- If the new horn requires splicing into airbag systems or other sensitive components
- For complex wiring routed through the firewall or other areas
- If specialized programming or calibration must be performed after installation
- If mounting locations are difficult to access without removing adjacent components
- For custom bracket fabrication or modification required to mount the horn
There’s no shame in calling for backup to ensure everything works correctly.
With proper planning and mechanical skills, upgrading to an aftermarket horn is an attainable project. Take time to do it right, and you’ll have a unique horn providing smiles for years. Others on the road may have different reactions, so use your fun new sound responsibly.
Stay safe out there, but let your horn speak for your personality! The open road awaits.