Перейти к содержанию

Electronic Handbrake: How It Works and What Breaks Down

Understanding how EPB is designed and why it's too early to write off the simple mechanical lever

Not long ago, a car without the familiar handbrake lever seemed unusual. Today, it's increasingly replaced by a small button, and the parking brake itself transforms into an electronic system. This design is called EPB (Electronic Parking Brake) and has gradually become common even in mass-market cars.

Manufacturers are abandoning the traditional lever not only for a modern appearance. The electronic mechanism takes up much less space, can work in conjunction with other electronic systems of the car, and frees the owner from some manual adjustments.

Image source: Chatgpt

But along with convenience comes another side: the design becomes more complex, maintenance is more expensive, and some familiar operations can no longer be performed without diagnostic equipment.

From Manual Lever to Button

The classic parking brake remained an extremely simple system for a long time. The driver pulled a lever, which, through a mechanism and cables, activated the rear brakes.

In American cars, another option was found – a pedal parking brake. The principle remained mechanical: no control units or electric motors were required.

The main advantage of this design was its simplicity. The cable could be replaced, the mechanism adjusted, and most problems could be solved by an experienced mechanic in almost any garage.

Electronic parking brakes began appearing in production cars in the early 2000s. Among the first cars with such a system were the 2001 Lancia Thesis, BMW 7 Series, and then the Lincoln LS, Audi A8, and Volkswagen Passat.

The technology then spread rapidly. By 2020, cars with mechanical handbrakes accounted for less than a quarter of new car sales in the UK. Brands like Honda, Lexus, and Mercedes had by then completely abandoned the lever in favor of electronic control.

In the Russian market, EPB appeared later. The first domestic car with an electronic parking brake was the Aurus.

Around 2020, UAZ also considered installing EPB for the new "Patriot". At that time, the technology was still perceived as quite unusual. Now the situation has changed: for many Chinese cars sold in Russia, the electronic handbrake has already become standard equipment. For example, new Geely Preface, Monjaro, Tugella, and Coolray receive EPB as standard.

What's Behind the Button

Two main designs are hidden under the name EPB.

Image source: Chatgpt

In the first case, an electromechanical system is used. There is a button in the cabin, but the mechanical part retains the cables. An electric motor activates the mechanism and tensions them instead of the driver.

The second option is arranged differently. Electric motors are installed directly in the rear brake calipers. After pressing the button, they move the mechanism that presses the brake pads against the discs. There are no cables or traditional linkages in such a system.

It is the fully electric scheme that has become widespread in modern cars. By 2026, it became a mass solution.

That is, the familiar hand movement has not completely disappeared – it has simply turned into an electrical signal. The driver presses a button, and electric motors and control electronics perform the further work.

How EPB is More Convenient Than a Regular Handbrake

The main and most obvious advantage is space saving.

Instead of a large lever between the front seats, the manufacturer only needs to place a small button. The freed space can be used for cup holders, a niche, or a wireless charging pad for a smartphone.

But the advantages don't end there.

One of the most convenient features is Auto Hold. It allows the car to hold itself in place after stopping. The driver does not need to constantly hold the brake pedal at a traffic light.

The scenario looks simple: the car stopped, the driver released the brake pedal, the car remains stationary. After pressing the accelerator, the system automatically releases the hold, and the car starts moving.

Another EPB capability is emergency braking.

If you press and hold the button on a moving car, the electronic parking brake will not just mechanically lock the rear wheels. The system interacts with ABS and ESP and slows the car down with stability control, reducing the risk of skidding.

This can be especially useful in an emergency, for example, if the driver has lost the ability to properly operate the pedals.

There is another difference from the old handbrake – automatic wear compensation. Electronics control the position of the brake mechanism and allow maintaining the necessary clearance between the pads and the disc.

As a result, the owner does not have to periodically tighten the cables themselves.

Where Problems Begin

The electronic handbrake has a significant drawback: convenience comes at the cost of increased design complexity.

One of the most well-known problems manifests itself in winter.

Image source: Chatgpt

If the brake mechanisms are wet after a trip, and then the car is left in the cold, the pads can freeze to the discs. EPB can create a strong enough force, so freeing a frozen mechanism can be difficult.

To reduce the likelihood of such a situation, it is recommended to dry the brakes with several light braking actions before a long stop in cold weather. In severe frost, some owners even prefer not to leave the car on the parking brake overnight if parking conditions allow.

What if the Battery Dies?

With a mechanical handbrake, the solution is obvious: the driver lowers the lever and releases the brake.

With EPB, it's more complicated. If the battery is completely discharged, the electric drives may not receive power, and the clamped brake mechanisms will remain in the same position.

In some cars, a mechanical emergency release is provided. However, access to it may be under the chassis, and the procedure will require tools and access to the brake calipers.

Therefore, in practice, in such situations, sometimes the car's power is first restored or voltage is supplied directly to the drive using an external source.

It turns out to be a paradox: a system that practically does not require driver intervention in normal operation can be much less convenient than an old mechanical lever in case of power failure.

Maintenance Becomes More Difficult

A regular handbrake has a relatively small set of potential malfunctions. For example, if a cable stretches or breaks, it can be replaced.

EPB introduces additional elements:

  • electric motors;
  • sensors;
  • electronic control unit;
  • wiring;
  • software adaptation.

Failure of one of these components can turn a relatively simple malfunction into an expensive repair.

This is especially noticeable when replacing rear brake pads. In cars with an electronic parking brake, it is often necessary to first put the system into service mode using a diagnostic scanner to retract the drive and be able to perform maintenance properly.

EPB is Not Suitable for Drift Enthusiasts

There is another fundamental difference that not all motorists will appreciate.

A mechanical handbrake allows the driver to intentionally use it to lock the rear axle and induce a skid. That is why the classic lever was an almost indispensable element for certain types of automotive entertainment and sports driving.

With an electronic parking brake, this scenario does not work in the usual way.

The system controls braking with electronics and ABS/ESP, so there is no longer a simple sharp lever movement to lock the rear wheels.

For normal operation, this is more of a plus. For those who use the handbrake not only for its intended purpose, it's an obvious minus.

So Which Option is Better?

There is no universal answer. The electronic parking brake perfectly matches the modern car concept: one button instead of a large lever, automatic hold, interaction with ABS and ESP, no need to manually adjust the cable.

For a new car like the Geely Monjaro or Tugella, EPB is quite logical. If the car is mainly operated in the city, the owner values convenience, does not intend to experiment with the handbrake in turns, and monitors the battery condition, the electronic system is more likely to simplify life.

Image source: Chatgpt

But the mechanical handbrake retains an important advantage – simplicity.

If the car regularly stands outside in severe frost, the brake mechanisms often get wet, the car can stand idle for several days, and you don't want to depend on electric drives and diagnostic equipment, the traditional mechanism still looks attractive.

Ultimately, the choice between EPB and a classic handbrake is not so much a question of which technology is "better" as it is a compromise between convenience and simplicity.

Electronics make the parking brake almost invisible to the driver. But the more functions a system receives, the more components are involved in its operation – and the more complicated the situation becomes when something breaks down.

Read more articles: