What is an Anti-lock Braking System (ABS)?

What do anti-lock brakes do?

An ABS makes it easier for you to steer in emergency braking situations by restoring traction to the tyres. By preventing the wheels from locking, an ABS can help the driver retain control of the vehicle.

How to use Anti-lock Brakes in an emergency?

To activate your car’s ABS, apply (and hold) pressure to the brakes. You should also steer to avoid any hazards, if necessary. Maintain pressure on the brakes until you have either slowed down to a safe speed or come to a complete stop.

Do I still need to pump my brakes when driving a car with ABS?

When driving an ABS-enabled vehicle, there is no need to pump your brakes. Your ABS will automatically pump the brakes the moment it detects wheel skid. All you need to do is apply firm, steady pressure to the brake pedal. The pedal should then pulsate while the ABS light illuminates.

Are anti-lock brakes a legal requirement?

Anti-lock braking systems have been compulsory for all production cars in the UK since 2004. Any car from the UK market built after this time will have ABS fitted as standard. ABS for new vehicles was made compulsory by EU law for safety reasons and has saved many lives since being introduced.

Can ABS be added to my car?

Yes, ABS can be retrofitted to virtually any car – and this should improve the vehicle’s safety as well as reducing the likelihood of accidents. This should be carried out by a reputable mechanic to ensure the system is correctly installed.

However, before committing to having an ABS added to your car, you should consider whether the work is economically viable. ABS conversions can be expensive and may even exceed the value of your car.

To help you determine whether this would be a worthwhile project, you can use our free car valuation tool. And, if you decide that selling your vehicle is the way forward, we can also arrange to buy your car.

How does an Anti-lock Braking System work?

The ABS senses when the wheels are about to lock, then reduces and adds braking pressure many times per second, so that the right amount of pressure is applied. This ensures the wheels continue moving as the vehicle slows, avoiding wheel lock.

When will my anti-lock brakes take effect?

Anti-lock brakes take effect when the sensors, placed by each individual wheel, detect that the wheels are about to lock.

What are the components of an ABS system?

An Anti-lock Braking System comprises four components, which work together to deliver more braking power and control:

Speed Sensors

The speed sensors, which are located at each of the wheels (or sometimes, the differential) are used to detect when wheels are just about lock up.

When are anti-lock brakes most effective?

Anti-lock brakes are most effective when applied firmly and promptly on dry, solid surfaces, and when the vehicle has good contact with the road. For your ABS system to work well, the tyres should also be properly inflated and in good overall condition.

When are anti-lock brakes least effective?

Anti-lock brakes are less effective when road contact is poor and on surfaces such as mud, snow or gravel. However, so long as the tyres and the rest of the vehicle are in good working order, your ABS should still provide enhanced braking control in these conditions.

Which vehicles have ABS?

All UK production cars manufactured since 2004 are fitted with ABS as standard, as this was made mandatory by UK law. Some models manufactured before then do not have ABS. However, many older models do have ABS fitted, as the technology has been available since the 1960s.

How do I know if I’m driving a vehicle with anti-lock brakes?

If your car has anti-lock brakes, you’ll notice the system working when you push the brake pedal down and the car judders as it slows. This is due to the ABS rapidly applying and releasing across all four wheels to avoid skidding.

Rear-wheel only ABS

Some older vehicles, particularly pickup trucks have rear-only ABS. Aside from being cheaper for manufacturers, rear-wheel ABS helped to prevent the lighter end of the vehicle from swinging during harsh braking.

Rear-only ABS was more common among cars in the US market, until full ABS became mandatory for all new production cars sold in the United States in 2013.

Pros and cons of ABS

Advantages of ABS

Cars with Anti-lock Braking Systems offer several advantages over those without. Firstly, they are far less prone to wheel lock and skidding, even in slippery conditions, where drivers may otherwise lose control. They are also highly effective in emergency stop scenarios, as the ABS will prevent the brakes from locking.

Thanks to the enhanced steering and braking control it provides, ABS technology can enhance your car’s value. And, thanks to the improved safety, many insurers offer cheaper rates for vehicles with Anti-lock Braking Systems.

Disadvantages of ABS

In most circumstances, anti-lock brakes provide a good level of braking control. However, stopping distances can be inconsistent on various surfaces and in differing conditions.

The sensors on each wheel can be costly to repair or replace should they become faulty. The electronic components are also sensitive and repair bills can run high if they become damaged.

The history of Anti-lock Braking Systems

The first ABS system was developed by Dunlop in the 1950s for aviation applications. It improved stopping distances when landing and virtually eliminated wheel lock. The first car with ABS was the 1966 Jensen FF, which was unwieldly, and the hydraulic system didn’t translate well to vehicular use.

However, as electronic technology improved, in the 1970s and 80s, more responsive ABS systems were available with models from popular manufacturers such as Bosch and General Motors. In 1985, the Ford Scorpio was the first car to be sold with ABS as standard across the entire range.

What is cadence braking?

Cadence braking (also ‘stutter braking’) is a driving technique for performing emergency stops that was widely taught by driving instructors before shrinking numbers of non-ABS cars on the road rendered it largely obsolete.

Is cadence braking still necessary?

Providing your car has a working ABS system, cadence breaking isn’t necessary. In an emergency stop situation, hit the brakes and the system’s electronics will handle the rest. Cadence braking is still useful for driving non-ABS vehicles, but switching to anti-lock braking is the safer option.

Other Frequently Asked Questions