(Updated on May 8, 2020)
Ever wonder how the electronics in your steering wheel maintain their connection when you can turn the steering wheel several times in each direction?
If normal wires were run to the steering wheel controls, they would eventually get tangled up and break, just from everyday use. This is exactly what a clock spring is designed to prevent.
Because the airbag in your steering wheel is dependent on a functional clock spring, it’s crucial that the clock spring is in good working condition. Keep reading to understand how a clock spring works, what symptoms of a broken clock spring are, and the average replacement cost is.
What is a Clock Spring?
A clock spring is a coil of flat wires wound inside an assembly in the steering wheel. One part of the outer assembly follows the steering wheel, and the other part attaches to the steering column.
This device is sometimes referred to as a spiral cable, airbag clock spring, steering wheel clock spring, clock spring assembly, cable reel, or contact reel, depending on the vehicle and where you live.
The clock spring is not really a spring at all, but it gets its name from the look of the coiled ribbon inside the housing. This coiled ribbon resembles the shape of a spiral torsion spring, but does not compress and release stored energy the way an actual spring would.
What Does a Clock Spring Do?
As you turn the steering wheel, the coil of wires within the clock spring winds and unwinds, maintaining an electrical connection for the airbag and steering wheel controls.
Regardless of how much you turn the steering wheel and in what direction, you always keep a connection between the airbag control module and steering wheel airbag, the radio and its steering wheel controls, the horn button and the car horn, and any other buttons or controls on the steering wheel to what they operate.
You may be thinking that the clock spring plays a role in returning the steering wheel to a neutral position, but this is not the case. The reason a steering wheel returns to its centered position when you let go of the wheel is because of the vehicle’s caster angle, not the clock spring.
Most vehicles have a positive caster angle. When the front wheels are turned, a positive caster angle puts force on the front tires that makes them want to return to their neutral position, pointed straight ahead.
Since the steering wheel is directly connected to the tires, the steering wheel is affected by this centering force. Besides, a real spring this small would likely not be able to overcome the inertia of most vehicles’ steering assemblies.
Where is the Clock Spring Located?
The clock spring is usually located on the steering column behind the steering wheel. Almost every road going vehicle with a steering wheel has one of these devices.
However, if your vehicle has no airbag, steering wheel controls, or horn buttons, you may not have a clock spring.
Bad Clock Spring Symptoms
Diagnosing a bad clock spring can often be pretty straightforward, depending on the symptoms. You may notice several seemingly unrelated issues, such as steering wheel buttons that don’t work accompanied with an airbag warning light.
Sometimes these components will work when the steering wheel is in one position, but stop working as soon as you touch or turn the steering wheel. An intermittent connection could manifest as a flickering warning light or sporadic, inconsistent functionality.
You may also hear a rubbing, scraping, or grinding noise coming from inside the steering wheel if the ribbon has disconnected from the terminals and is rubbing against the side of the housing.
In some cases, a frayed or broken ribbon cable could get stuck between each half of the clock spring’s casing, which would make the steering wheel a bit harder to turn.
If you notice these symptoms it is best to address the issue as soon as possible. A bad clock spring can afflict you with more than broken volume controls.
You could be left without cruise control, a functioning horn, or most importantly, a functioning airbag. In this situation, you would be unable to alert an inattentive driver and the airbag may not deploy in the event of a collision.
Some vehicles also use the angle of the steering wheel for traction or stability control calculations. A broken clock spring will leave these systems in a degraded state, if they continue to function at all.
Clock Spring Replacement Cost
Clock springs are relatively inexpensive, running between $50 and $200 depending on the vehicle. Labor is fairly straightforward and should take 1-2 hours; expect to pay up to $300 in labor.
If you attempt to replace the clock spring yourself, it is very important that you follow the manufacturer’s instructions for safely disabling the airbag. Failure to do so could lead to an airbag detonation that may cause serious injury or death.
Consult your vehicle’s factory service manual for details on this procedure. At the very least, the instructions will likely ask you to disconnect the battery and wait at least 10 minutes to ensure the airbag system has been disarmed.
See Also: Average Airbag Replacement Costs
Can a Clock Spring Be Repaired?
While it is sometimes possible to repair a damaged clock spring, it is generally better to buy a new one.
Clock springs are cheap, and it’s important to have a reliable unit since they may be involved with the correct function of the driver’s airbag, the horn, cruise control, and traction and stability control systems.
Can You Re-use a Clock Spring?
If you remove the clock spring while performing a repair, it is often possible to reuse the clock spring. Remove the clock spring while the steering wheel is in a neutral position and be sure not to turn the clock spring after you remove it. Reinstall the clock spring in the same neutral position.
If you were to spin the clock spring a rotation or two and then reinstall it, you may not have enough slack in the internal ribbon before the steering wheel hits full lock. In this case, you run the risk of stretching or breaking the internal wires and damaging a perfectly good clock spring.
If the airbag has deployed, it is best to replace the clock spring with a new unit.