7 car dashboard warning icons you need to know about

It's never nice when a warning light appears on your car dashboard, particularly if you're left wondering what it actually means – but our experts are here to help.

To help you make sense of the most common car faults, we've rounded up a selection of dashboard symbols and notifications worth familiarising yourself with. You can watch our video on this page or keep reading to find out what each warning means and what to do next.

If you're tired of spending big on repairs and are thinking about replacing your car, make sure you consult our expert car reviews. Below, you'll find more details on our rigorous lab tests and how we're able to identify the most reliable car brands.

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1. Brake warning light

This icon will usually be displayed as an exclamation mark or the word ‘BRAKE’ inside a circle. If the brake warning light stays on after you release the handbrake, or comes on after you start driving, your brake fluid (also known as hydraulic fluid) might be low. Other possible causes include worn brake pads or a faulty sensor.

Assuming the light pops up while you're driving, pull over safely as soon as you can – driving further could potentially lead to brake failure. You can either check the brake fluid yourself or get a professional to take a look.

To check the brake fluid yourself, open the bonnet and locate the brake fluid reservoir. If you're not sure where it is, consult your vehicle’s manual for step-by-step instructions. Markers on the reservoir will tell you if your car needs a top up.

A 1-litre bottle of brake fluid typically costs around £10, but check your car's manual first to find out what type it requires.

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2. ABS warning light

Your car’s ABS (Anti-lock Braking System) is designed to prevent the wheels from locking up if you brake hard, helping you maintain control – especially on wet or slippery roads. As you press the brake pedal, the system monitors the rotation of each wheel. This key safety feature activates during emergency stops.

If you're seeing an ABS warning light, the system might not be working properly. While you'll still be able to brake while you're driving, you're more likely to skid as a result, particularly at high speeds. This issue needs checking by a professional as soon as possible.

3. Engine warning light

You'll see this symbol on your dashboard if there's a potential problem with your engine. It can also be displayed as a "check engine" notification.

This could be something minor, like a faulty sensor, or a more serious mechanical problem, so get it checked out as soon as possible.

In some cases, you might notice that the warning light appears when you start your car and then turns off again. This could mean that you're still able to drive while you get it resolved. However, if the symbol is permanently illuminated or flashing, this may indicate a more serious problem that requires immediate attention.

If you need help with your car, visit Which? Trusted Traders or use the search tool to find a recommended mechanic near you:

4. Battery warning light

This indicates that your battery isn’t charging, so ideally, you should get to a garage as soon as possible.

However, seeing this symbol doesn’t always mean the battery is at fault – the issue could be with the alternator instead. The alternator’s job is to recharge the battery while the car is running by converting mechanical energy into electrical energy, using a belt connected to the engine.

Either way, you’ll need to consult a professional to get the issue sorted.

If your battery is flat or if you just need a refresher, consult our guide on how to care for and jump-start your car battery.

5. Oil warning light

This indicates that the oil pressure is too low or the oil temperature is too high, both of which can quickly damage your engine. To top up the oil yourself, locate the oil filler cap and check the levels using the dipstick. If you're unsure, refer to your vehicle’s manual for instructions.

If the warning light goes off after topping up the oil and you don’t notice any leaks, it’s generally safe to continue driving.

However, if the light remains on or you notice leaks, call for breakdown recovery.

6. Tyre pressure warning light

This means that at least one of your tyres is under-inflated. If the warning appears while you're driving, you'll need to avoid sudden braking and top up the pressure at a petrol station or garage.

Damaging a tyre by striking an obstacle will, unsurprisingly, cause it to deflate quickly. You’ll likely feel a tug on the steering wheel and will probably hear it as well. If the tyre is deflating slowly, the steering may just feel heavier than usual, or drag to one side. (see also: How to change a car tyre)

Invest in an air compressor if you don't already have one tucked away in your boot. Most plug into your car's 12v socket, and there are plenty available online for under £20.

For more information on when you should think about replacing your tyres, see our guide: Which car tyres should I buy?

7. Airbag warning light

This light indicates that one or more airbags may not be functioning properly.

In a collision, faulty airbags could fail to deploy – or worse, they might go off unexpectedly while you're driving. Either way, this is a serious safety issue that needs to be checked by a professional immediately.

Car brands you can rely on

To uncover the car brands that stand the test of time, we survey thousands of drivers each year and ask about any problems they've experienced with their vehicles.

The issues covered in our survey can range from minor faults to catastrophic failures. We use the results to identify which brands make the most and least reliable vehicles.

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For more details, see our guide to the most reliable car brands. Alternatively, discover the best cars.