The most common UK car breakdown causes revealed: How to avoid the dreaded hard shoulder

As the days begin to get longer and more families prepare longer road trips for their summer holidays, it’s important to keep on the lookout for signs that your car may be struggling with a problem. Fortunately, there are plenty of quick and easy ways to lower your risk of becoming another unwanted breakdown statistic.

In 2024, there were 282,949 breakdowns on British motorways, with some causes becoming more prevalent than others. But what reasons were the most common for breakdowns? The AA has created a helpful list to provide insights into what’s been harming UK cars the most.

While some of the most common causes of breakdowns, like using the wrong fuel and lost keys are more down to forgetfulness and lapses in concentration, other breakdowns can be more challenging to keep on top of.

With this in mind, let’s take a deeper look at the most common breakdown causes and how to avoid them:

1. Battery problems

The most common form of breakdown in the United Kingdom is due to a faulty or flat battery. 12-volt battery faults, particularly in the winter months, can affect petrol cars, as well as diesel, electric, or hybrid vehicles.

Flat batteries can be caused by a lack of use or too many short journeys. Faults can also arise due to poor electrical connections.

Additionally, you may find yourself with a flat battery if you leave any of your in-car electrics on after you finish a journey, and it’s for this reason that you always check to make sure you’ve turned your lights off when you leave your vehicle.

To avoid a flat battery, it can be worth taking a long journey with your car once in a while. This gives it more time to charge while in motion. If your car’s only a runaround, it may be worth buying a battery maintainer to charge it overnight.

Whenever your car gets serviced, your battery should be checked for signs of corrosion and possible faults, but you should still stay vigilant if something doesn’t seem right.

2. Wheel damage

Damaged wheels and tyres are more common than other parts of your vehicle because they have constant contact with the road below and are far more prone to wear and tear.

Problems can easily arise in your wheels and tyres if you’ve hit a pothole or deep curb, your tyre tread has become worn, your tyre and rim have separated after a collision, or you’ve received a slow puncture from a sharp object.

Here, you should always have a spare wheel on all the journeys you take and a portable air pump can be really handy if you find that your tyres are dangerously flat.

Flat tyres can lead to all kinds of problems when controlling your vehicle, and if you hit a pothole with an underinflated tyre, it’s more likely to cause damage to your chassis and suspension.

Similarly, you should seek your local windscreen repair and replacement specialists if you have any cracks. This is because they can spread and become a hazard in a similar way to underinflated tyres.

3. Incorrect engine oil levels

Another issue stems from having the incorrect level of engine oil in your car. While it can be tempting to overfill your oil levels to keep things running for longer, too much engine oil is just as dangerous as not having enough.

Particularly for diesel car owners with a DPF, your oil risks becoming diluted if the DPF regeneration fails to happen. This can lead to severe engine damage and requires an immediate oil change at your nearest garage.

Fortunately, you can easily check your engine oil levels with a dipstick. As long as the level falls within the two specified lines, your vehicle should be safe from any oil-related errors.

While it’s possible to refill low engine oils yourself using the values given in your vehicle handbook, it’s worth visiting your garage if you’re unsure of what to do.

4. Timing belt failure

Timing belts, or chains, are a key part of your engine, and any failure can cause irreversible damage.

This breakdown cause is usually down to a lack of oil, or oil degradation, meaning that regular oil changes and maintaining the right levels can help your timing belt to last longer.

It’s issues like timing belt failure that make regular servicing and the following of manufacturer recommendations on replacements highly important for drivers–particularly of older vehicles.

If something’s wrong with the timing belt, you may hear some unusual noises coming from your engine. Should you hear anything new or concerning, it’s worth checking with your garage immediately.

5. Alternator issues

Alternator issues can be a serious problem for drivers, and if you’re seeing symptoms like dim headlights when your engine is idling, it might mean that your alternator is experiencing issues.

If you suspect that your alternator is having problems, you should give your garage or breakdown company a call as soon as possible.

Additionally, if you’re seeing your ignition warning light come on and rapidly rising engine temperatures, it might mean that the belt driving the alternator and water pump is broken. Again, this issue is serious and requires immediate attention.

Keeping your car safe

It can be a challenge to keep your car safe when you’re not always sure of what you’re looking out for. However, it can be as simple as acting on a strange noise or keeping an eye on any dashboard alerts.

Thankfully, newer cars are becoming more functional when it comes to alerting drivers to problems, but it still pays to act on any concerns fast, even if your car hasn’t handed out a warning light on the dashboard.

As those summer months come back around, your car may begin to get more use as the days become longer. To enjoy your warm weather trips without incident, get your car serviced or keep on the lookout for anything that doesn’t seem right well in advance.