What do you do if your car horn goes off in the middle of the night? Do you keep driving and ignore the issue since you don’t see it often? As a driver, you need to treat horn problems the same you would do for brakes and headlight failures.
Your car horn might go off all of a sudden for several reasons. In this post, you will read about the significant causes of horn failure and the possible solutions.
4 Reasons Why Car Horn Goes Off
If your car horn goes off suddenly, check the horn relay, steering wheel airbag, horn switch, and electrical connections in the horn system. Each cause requires a specific solution to get it fixed.
The sound from the horn going off suddenly is louder than the lawn mower-like noise that your car may have sometimes. So please check the potential causes for this issue and learn how to deal with each.
Horn Relay
If your car horn keeps going off randomly, check the horn relay first as it is the most common cause.
The horn relays often rest under your car hood or on the firewall. Unfortunately, these positions are prone to weather conditions. And when exposed to moisture, the horn replays will malfunction, making your car horn go off suddenly.
How to solve it?
Once you notice the malfunction in the horn relays, detach the wire connecting to the horn to check them.
If you have a friend with you, ask them to press the horn button. In the process, be attentive to clicking sounds or noises. If there are any, you will have to replace the horn relay.
Luckily, a horn relay only costs around $10 to $15, and you can replace it yourself. The instructions are as follows:
- Find the horn fuse in your car’s fuse box. The owner’s manual or the diagram on the fuse box cover can help you locate it quickly.
- Open the cover to reveal the relays and fuses.
- Find the relay at the location demonstrated in the diagram.
- Remove the relay by grasping it and pulling it out of the socket. It will come out easily.
- Install the new relay. It can only fit if you insert it in the correct orientation.
- Finish this DIY project by closing the fuse box cover.
- Test if your car horn can work properly.
Malfunctioning Steering Wheel Airbag
If your car horn is going off for no reason, the next thing to check after the horn relay is the steering wheel airbag.
Usually, due to the heat, the outer plastic cover of the airbag gets distorted, and when it cools down during the night, it gets into contact with the horn. The contact leads to an electric short, eventually forcing the horn to go off.
How to solve it?
To solve this, you will need to make a replacement for the malfunctioning steering wheel airbag. Be ready to spend as it is not cheap to change the airbag, plus you will have to pay for the labor charges.
Faulty Horn Switch
The horn switch activates the car horn when you press the button. If it malfunctions, the electrical circuitry will halt. Then, the car horn goes off in the middle of the night.
How to solve it?
A qualified mechanic can help you diagnose the issue and replace the malfunctioning components in the horn switch. Then, the horn can work properly.
Loose Electrical Connections
What if you still cannot figure out the cause after trying all the above troubleshooting tips? Then there is a possibility that your car has broken or a poor wire connection, leading to the problem.
The electrical connections in your vehicle’s horn provide power to the horn whenever you press the button. The circuit can’t work properly if they become loose over time or broken. As a result, your car horn may go off suddenly.
How to solve it?
The horn-related problems don’t often make your car unsafe. But you should still pay attention to them.
So, take your time and examine the chafed wires. Not everyone is good at tracking wiring problems in the car. If you cannot do it on your own, then it will be wise to reach out to your mechanic to solve the problem.
How To Stop A Car Horn From Going Off?
Before arriving at the nearest garage to ask for help, the loud noise of the horn must annoy you. Pulling the horn relay or fuse is the fastest way to silence it.
If you can’t find the correct relay or fuse, disconnecting the car battery or taking off the main fuse can also help you stop the noise.
Be careful when handling the wiring as it is dangerous. If you are not confident of your automotive knowledge, do not rush yourself.
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Is It Safe To Drive With A Car Horn Going Off Suddenly?
The horn going off seems to annoy your driving with its loud noise. However, it’s not something you can ignore.
First, the sudden noise may startle you and other drivers. You will, therefore, lose control of your vehicle, potentially leading to an accident. Imagine how irritating it is when the neighbors car horn keeps going off, and how it wakes you up at night.
Second, you should be careful if the horn issue comes from the loose wire connections. There is a short circuit risk if the exposed wires of the horn touch the ground.
Conclusion
If your car horn goes off, the cause can be the malfunctioning parts of the horn system. Faulty horn relay, switch, and loose connections will contribute to the issue. The problematic steering wheel airbag is another possible cause to check.
After finding the cause, perform the above steps to solve your problem. Then, you will be confident driving on the road with a horn that will scream whenever you need it.

Hi! My name is Mark Stevens – the founder of Auto News Portal.
I wrote articles in the automotive industry for more than 10 years, published in USA, Europe and the Asia. I love sharing my knowledge and insights with fellow enthusiasts. Join me on this journey as we explore the exciting world of cars together!