horn assembly replacement

What does a horn assembly do?

When the horn button (usually located in the centre of the steering wheel) is pressed, an electrical signal is sent to the horn relay, allowing power to flow to the horn(s) which are often located under the bonnet. This circuit is known as the horn assembly.

A functioning horn is an essential safety component of any vehicle on the road. As a driver, you’ll use the horn to warn others of your vehicle's approach or presence, or to call attention to a hazard on the road. In fact, if your horn is missing or broken and does not sound when pressed, then this will result in an MOT failure. So to avoid hassle and money in the long run, it's best to have a broken horn replaced as soon as possible.

How often should a horn assembly need replacing?

In an ideal world your horn assembly should last the lifetime of the car, but there are instances where this is not the case. Just like any other electrical component in a vehicle, there will be times when the horn will need replacing due to corrosion, bad wiring, water damage or a faulty relay.

The law, vehicle regulations and your MOT

The functionality of your car horn will be checked as part of your MOT. A faulty or quiet horn is classed as a minor on the test, however if your horn is inaudible to other road users this will result in an MOT failure. To avoid the hassle and cost of an MOT fail, it’s best to have your horn fixed as soon as you notice an issue.

What causes a horn assembly to break?

Car horns are located just under the bonnet so they’re exposed to rain, debris and other nasties. If this dirt or rain gets into the horn’s innards, it can short out the circuit and break the vehicle horn (and blow the fuse in the process). However, a horn assembly consists of multiple components which could also affect the functionality of the horn. For example, a broken car horn can also be caused by a bad horn switch in your steering wheel, a broken “clock spring” under the steering wheel, a faulty horn relay, or bad wiring.

When should a horn assembly be replaced?

As soon as you notice that your horn is not as loud as it used to be or if there is no sound at all, you should have the horn assembly looked at by a mechanic as soon as possible. Without a working horn you could be a danger on the road and your car will almost certainly fail its next MOT.

What are the signs of a bad horn assembly?

Usually, there a few signs you can look for:

• Your horn makes no sound when the button is pressed

• Your horn is too quiet to be heard by other road users

• Clicking sound from the horn relay

• Burning smell from under the bonnet

What happens during a horn assembly replacement?

During the repair our certified mechanics will:

• Inspect the entire horn assembly and identify the part(s) that need replacing

• Disconnect the battery

• Replace the necessary parts, either the button, relay or the horns

• Reconnect the battery and test the horn

What is the average lifespan of a horn assembly?

A horn assembly is built to last the lifetime of the car, but there are instances where this is not the case. Just like any other electrical component in a vehicle, there will be times when the horn will need replacing due to corrosion, bad wiring, water damage or a faulty relay.

Can you drive with a broken horn assembly?

No, you should get your car horn fixed to ensure you are safe on the roads. It is both unsafe and illegal to drive with a broken horn, as it is an essential safety feature in your car. Failing to replace a broken horn will also result in an MOT failure.