Airbag Light On and Horn Not Working? You Might Have a Broken Clockspring

It’s not uncommon for customers to call us saying, “Why is my horn not working?” We will usually respond by asking about the cruise control button not working as well and if the airbag light is on.A malfunctioning cruise control, the airbag light on, and the horn not working nearly always point to a broken clockspring. You may not even know about this clever part in your vehicle. But it’s an essential component of several safety features, so if it breaks, you need to get it diagnosed and fixed as soon as possible.

Image by Toby Parsons from Pixabay

What Does the Clockspring Do on a Car?The clockspring is a relatively simple device that performs a vital service. It typically sits somewhere in or between the steering wheel and steering column. You might see this part spelled as two separate words (“clock spring”), and it may go by a few other names, including:

Spiral cableContact reelClockspring coilCoil spring unitCable reel assemblyCoil assembly

It’s usually black or yellow and shaped like a circle, with wires emanating from it that go further into the steering column. There are several different clockspring mechanisms depending on the age and make of the vehicle. But they all perform the same function.What does a clockspring do in a steering column? The clockspring allows your steering wheel to turn without breaking various wires in the electrical system that connect to features operated from the steering wheel or running through the steering column. It also sends signals from the wheel to your horn, often through the car’s or truck’s computer.What Are Signs of a Broken Clockspring?What will a bad clockspring do? Not surprisingly, if it’s broken, many of the features it enables will no longer function. Symptoms of a malfunctioning clockspring include:

Horn not working when you press the buttonAirbag light on, meaning the airbag may not deploy in a crashDifficulty steering (may be confused with a power steering problem)Rubbing or clicking noises when turning the steering wheelProblems with consistent speed or accelerating

The issue with the last item on the list above is because the clockspring participates in the function of the throttle position sensor. A bad clockspring can send electrical spikes to this part, affecting engine performance.Some vehicles have other features that can be controlled on the steering wheel for extra convenience and may also not work from the wheel with a broken clockspring but will run from another location. Examples are:

Heating and air conditioningRadio/CD playing and volumeGPS and navigationTelephone connection4-wheel drive on/offDriver assistance technology

In fact, the steering wheel has become such a command centre for functions — replacing the dashboard — that some vehicle manufacturers have patented their steering wheel control systems.What Causes Broken Clocksprings?Clocksprings usually break for one of three reasons. In older or high-mileage vehicles, wear and tear can cause the clockspring to stop working. If you have a combination of the symptoms listed above and the next two symptoms below don’t sound right, you should probably have your mechanic see if it needs replacing.Another common reason for a broken clockspring is airbag deployment. Usually, the clockspring doesn’t so much break as melt due to the heat of the chemical reaction involved in an airbag deploying. Airbags use what is essentially rocket fuel to emerge from the steering wheel in a split second following significant impact.If you’ve recently had a crash and had the airbag reset, the clockspring should have been replaced. But some bargain basement mechanics or DIYers forget to do this. That’s why you should always have a trusted mechanic who knows what they’re doing take care of any airbag problems for you. That’s one place where you don’t want to save a few dollars, as it could cost you — with your life — in the long run.The third cause of a broken clockspring is making a super tight turn, like a U-turn, that pushes the natural turning radius of the vehicle. Older cars with worn clocksprings are particularly vulnerable.Drivers almost always know when the clockspring breaks suddenly like this, as one minute everything is operating normally, and the next your horn doesn’t work and your airbag light is illuminated. You may also hear unusual noises from the steering column.Should You Call Your Mechanic if You Suspect a Broken Clockspring?Your horn and your driver’s side airbag are two of the most important safety elements of your vehicle. Therefore, if they’re not functioning due to a broken clockspring, you are increasing the risk of accidents and injuries. You could also be cited by law enforcement around Langley, BC or in the States if you venture south of the border.