Car Warning Lights

Dashboard warning lights – What do they mean?

Everything you need to know about car dashboard symbols and meanings

Engine warning light head

Wondering what those symbols on the dashboard mean? The warning lights on your car's dashboard light up when something's wrong. As a rule of thumb:

  • Red warning lights mean you need to take immediate action.
  • Amber warning lights (or other colours) often mean something needs checking by a garage
  • Green lights mean everything is OK

It’s normal to see some of these lights briefly while you start your engine. But if they stay lit up while you’re driving, then you'll need to look into it.

Car dashboard symbols and meanings

This handy guide lists the most common car warning lights our mechanics are asked about. Choose from the symbols below to find out what to do next:

If you can't see the symbol you're looking for, check your owner's manual as warning icons vary with each manufacturer. Or use our free app to search all warning lights by car make and light colour.

Find out more about how breakdown cover can help you if you have car troubles in our breakdown cover guide.

What is the most serious car warning light?

The red oil warning light is the most serious if it comes on when the engine is running, as this means the engine has lost oil pressure and a failure is imminent.

The check engine warning light is also generally considered to be one of the most serious dashboard symbols. If it lights up, it could signify potentially serious damage, so it’s important not to put off getting your car checked if this happens.

If you ignore check engine warning light, it could lead to a blown head gasket or a seized engine, meaning the end of the road (at least temporarily) for your vehicle.

Can I drive with the engine warning light on?

If your check engine light comes on and you have no alternative but to continue driving (for example, you might be on a smart motorway), try to drive as carefully as possible to get somewhere safe and have your vehicle checked at the earliest opportunity.

We wouldn’t recommend driving more than a couple of miles once the warning light has come on. You should also avoid heavy acceleration and high engine speed.

What could cause the check engine light to come on?

There are, unfortunately, more reasons for a check engine warning light than you’d care to shake a stick at. Some of the main culprits are the following:

  • Oxygen sensor malfunction
  • Blocked diesel particulate filter
  • Mass airflow sensor
  • Ignition system fault
  • Loose oil dipstick

For more in-depth information on what can cause that dreaded light to turn on, visit our engine management light page.

Dashboard warning lights and what they mean

Engine managementEngine

BatteryBattery

OilOil

BrakesBrake

ABS

ABS brake

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Filter

 

 

 

 

 

 

 

 

 

If you can't see the one you're looking for, check your owner's manual as warning icons vary with each manufacturer. Or use our free app to search all warning lights by car make and light colour. 

Find out more about how breakdown cover can help you if you have car troubles in our  breakdown cover guide.

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Engine management

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Engine management light

Safe to drive?

Yes – if it’s always lit and there's no loss of power. You should get it checked as soon as possible.

No – if it's flashing while you're driving. Avoid heavy acceleration and high engine speed. Stop the vehicle when it's safe to do so. Restart the engine after 2 minutes to reset the engine management system. If the light's still flashing, turn off the engine and contact us to report your breakdown.

Next steps

Get a garage to check the engine soon to avoid damaging the catalytic converter or diesel particulate filter.

The problem

Cars have lots of sensors to check if everything's running smoothly. If there's a problem, the sensor will tell the engine control unit (ECU) which will turn on the engine management light. There are many reasons why the light will show but a garage can check what the cause is.

Learn more about engine management lights and what causes them to turn on. 

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Battery

Battery warning light

Safe to drive?

No – if the battery light's red while you're driving, you need to have the fault looked at immediately as the battery isn't charging.

Next steps

Stop the vehicle in a safe place, turn off the engine and contact us to report your breakdown. Don’t restart the engine as this could make the problem worse.

The problem

There may be a problem with the wiring, the alternator or the alternator drive belt. You may simply have a flat battery.

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Oil

Oil pressure warning light

Safe to drive?

No – you need to stop and check your oil level. This light shows when there's no oil pressure in the engine.

Next steps

Stop as soon as you can and check the oil level, topping up as needed. Your owner's manual will tell you how. If the light still shows, turn off the engine and contact us to report your breakdown.

The problem

If the warning light's on when the oil level's right, there's a problem with the oil supply. That could be caused by the oil pump or a blocked oil filter. Your car engine needs the right oil pressure to stay lubricated, otherwise it'll get damaged.

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Brakes

Brake warning light

Safe to drive?

No – if you need to press your brake further than usual, your hydraulic brake circuits may have failed. Pull over and get help.

Yes – if the brake fluid level's OK, it might just be a sensor fault. In that case, it's safe to drive to a garage.

Next steps

Check you've released the handbrake fully. If you have, stop, check the brake fluid level and top it up if you need to. Your owner's manual will tell you how.

The problem

Your vehicle may have a brake fluid leak, a sensor failure or need the brake pads replacing. Get it checked out at your local garage.

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ABS brakes

Anti-lock braking system (ABS) warning light

Safe to drive?

Yes – for most vehicles, as long as there aren't any noises coming from the wheels. Check your handbook to be on the safe side. Take extra care when driving, especially during wet or icy weather, as your car's braking distances may increase.

Next steps

Get a garage to check the ABS system as soon as possible.

The problem

It could be as simple as a sensor fault but a garage will let you know what the issue is.

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BrakesABS brakes

Brake system and ABS warning lights

Safe to drive?

No – stop the vehicle and contact us to report your breakdown.

Next steps

Slow down gradually and avoid braking suddenly.

The problem

If your brake and ABS warning lights come on at the same time, there could be a major fault with the brakes. This is unsafe for you and other road users, so don’t drive the car until the problem has been looked at and fixed.

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Diesel particulate filter (DPF) warning light

Safe to drive?

Yes – but you should drive for around 10 minutes at over 40mph when safe.

No – if the light doesn't disappear after continual driving. In that case, stop the vehicle, turn off the engine and contact us to report your breakdown.

Next steps

Stop-start driving can cause the DPF to get blocked. To clear it, drive around for 10 minutes at over 40mph. Check your owner's manual for more specific advice.

The problem

The DPF traps tiny soot particles which are harmful to health, and converts them to harmless ash when the exhaust system gets hot. But this doesn't happen on short journeys. If the DPF is full, it'll need replacing, which can be expensive.

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Airbag warning light

 

 

Airbag warning light

Safe to drive?

No – an airbag is a potentially life-saving safety feature that you wouldn’t want to be without. You (hopefully) might not ever need it to deploy, but that’s not a reason to ignore the airbag warning light. Get your car checked at a garage as soon as possible.

Next steps

The good news is that fixing or replacing an airbag is a relatively simple task that any good garage/mechanic should be able to sort out for you.

The problem

There could be a problem with the supplement restraint system, which links the seatbelts to the airbags. There may also be damaged wires under the seat, or a manufacturing fault with the airbag itself.


Power steering warning light

 

 

 

Power steering warning light

Safe to drive?

No steering is a vital aspect of driving. If a fault becomes serious and you lose control of your ability to steer, you could be involved in an accident.

Next steps

It’s best to get this one checked out by a mechanic as soon as possible. Drive carefully to the nearest garage for a full diagnosis.

The problem

The most common cause for vehicles that have hydraulic power steering is a problem with fluid levels, usually caused by a leak in the system.


Engine temperature warning light

 

 

 

Engine temperature warning light

Safe to drive?

No – if the temperature warning light is red, you’ll need to pull over somewhere safe and check your coolant levels.

Next steps

If you’re able to top up immediately you should do so. Try driving again and see if the light still comes on. If it does, you’ll need to get your vehicle checked.

The problem

The most common reason for this light to appear on your dashboard is low engine coolant levels. However, there could also be a more serious issue with the cooling system in your vehicle, so keep an eye on the dashboard once you’ve topped up your coolant.


Tyre pressure warning light

 

 

 

Low tyre pressure warning light

Safe to drive?

Yes – but only to complete your journey or drive to a garage. When this warning light comes on, it means the pressure in your tyres is getting low and they may be underinflated. If you ignore the warning, you could have tyre failure. You may also notice that you have reduced control over steering.

Next steps

Your dashboard may tell you exactly which tyre has an issue (depending on your vehicle) so you can pump air into it and try driving again. If you drive for a while and the light comes back on, this may show that you have a slow puncture, in which case you’ll need a replacement.

The problem

Often there’s a puncture to the tyre or just a gradual loss of pressure through use over time.


Esc warning light

 

 

 

Electronic stability programme (ESP) system light

Safe to drive?

Yes – in most vehicles, the ESP will come on (usually flashing) when you’re driving on a slippery or wet road to show you that the system is working as intended.

No – If you’re driving on a normal road in normal conditions, the ESP warning light coming on could signify an issue with the electronic stability programme system. The ESP system light is another critical safety that helps you avoid losing control or skidding while driving. An ESP warning light should be investigated ASAP.

Next steps

You can continue driving as you normally would if the light only flashes while you’re driving on wet or slippery roads. If the light keeps coming on in normal driving conditions, get your vehicle checked by a mechanic.


Brake pad warning light

 

 

 

Brake pad warning light

Safe to drive?

No – When brake pads get too worn, they won’t be able to do their job properly anymore (stopping your car when you hit the brakes).

Next steps

Take your car to the nearest garage as soon as you can, you’ll most likely need replacement brake pads.

The problem

Over time, brake pads can become worn naturally. Worn-down brake pads are thinner and, if left to worsen even further, could cause damage to the rotor.

 

Diesel car dashboard symbols and meanings


Diesel vehicles work differently and therefore have some of their own unique warning lights. Warning lights exclusive to diesel cars include the following:

  • Glow plug indicator

Glow plug warning light

 

 

This indicates that the engine’s glow plugs are warming up. It’s not recommended to start the engine until this light goes out.

  • AdBlue tank empty

Ad blue warning light

 

 

This light simply shows that you need to fill up the AdBlue tank.

  • Fuel filter warning

Fuel filter warning light

 

 

This means that the diesel fuel filter is full. It should be emptied to avoid damage to the engine.

  • Water fluid filter warning

Water fluid warning light

 

 

Another one for the fuel filter, this light means that you’ll need to empty out water from the system.

  • Exhaust fluid

Exhaust fluid warning light

 

 

Indicates that the diesel exhaust fluid reservoir is getting low.

  • AdBlue malfunction

Another AdBlue light – meaning the system itself has malfunctioned or is full of the wrong liquid.

 

Can I drive with a yellow warning light?

A general rule of thumb to follow with warning lights is that a yellow/amber light is warning you of a problem that needs to be checked. While you don’t need to stop driving immediately, you should get the problem checked as soon as possible. With red warning lights, you shouldn’t drive your car at all. Call your breakdown cover provider out to investigate the problem.

What is the most common colour of a dashboard warning light?

You’ll get green dashboard lights that show certain systems are working correctly, so technically we’d expect to see these appear more often than the red or yellow/amber warning lights that signify a serious problem with your vehicle.

What are the most serious car warning lights?

The most serious car warning lights are the check engine light, the oil pressure warning light, and the brake system and ABS warning lights. All of which can lead to critical problems with your vehicle if ignored.

How to reset or turn off car warning lights

You can try turning off your engine and restarting it to see if the warning light still comes on. However, warning lights should be taken seriously. Your first thought shouldn’t be to reset them or ignore them, rather, get them checked by a mechanic or your breakdown cover provider.

Find out more:

Find out what your car's really saying

Just plug our AA-X device into your car to get updates about your car’s health sent to your phone.

It helps you spot problems before they become a real issue and explains what to do about common warning lights. 

You can also learn what to do if you break down.


Last updated: 31 July 2024 | Author: The AA

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