What Do Car Dashboard Warning Lights Mean? (And How to Turn Them Off)

The sudden appearance of a warning light on your car dashboard can be a cause for concern - but it can also help you to take good care of your vehicle and prevent unexpected breakdowns.

In this article, we tell you what some of the warning lights on your car’s dashboard mean, and how to turn them off. 

 

Warning Light Colours

Green - If a warning light is green, this means that everything is working as it should. This can also mean that the system is in use. 

Yellow - A yellow warning light can indicate that something isn’t working properly, and you should have this checked out.

Red - If the warning light is red, you need to stop driving as there could be something seriously wrong. Pull over at the next safe place to stop, and call for assistance. 

 

Airbag Warning Light

The airbag warning light looks like a person reclining in a car seat, facing a big circle. When this light comes on, it means that an issue has been detected in the airbag system.

You should have your vehicle checked out by a mechanic as soon as possible.

if your airbags aren't working properly then they won't deploy if you are involved in an accident.

Airbag issues could stem from faulty sensors or wiring, or even a drained battery.

A garage will be able to run a diagnostic test and find the source of the problem for you.

If you notice this light whilst out driving, we would recommend that you drive sensibly and pull over when it is safe to do so - you can then call a garage or breakdown service to help you.

 

 

Anti-lock Brake System (ABS) Warning Light

The anti-lock brake system warning light displays the letters ‘ABS’ in a circle and a surrounding bracket.

This system is designed to prevent skidding, by helping you to limit the amount of pressure being applied to the brakes.

This light may appear if there are low levels in the fluid reservoir, issues with the ABS module or wheel speed sensors, or if the system itself is currently turned off.

A garage will be able to diagnose the issue and resolve it for you.

If this light comes on whilst you're driving, leave enough space between your car and those around you and it should be safe to proceed - though of course you should have this checked out soon.

However, an accompanying brake warning light could mean your vehicle is experiencing brake system failure, in which case you should pull over and call for assistance. 

 

Battery Warning Light 

A battery warning light can look like a battery pack, with a plus and minus on it. When this light is shining, this can indicate that your battery is no longer charging properly, or is on low charge.

You should pay special attention to this light if it appears when you turn on the ignition, or whilst driving - you may need to book in for a diagnostic check if this is the case.

If you notice that the light is yellow/amber or red whilst out driving, then you need to do something about this.

Drive sensibly to the nearest garage if you can - you may struggle to restart your vehicle, so your only other option is to pull over where it is safe to do so and call for assistance. 

You may need to have your battery replaced if the issue cannot be resolved. 

In some cases, the alternator may be to blame, instead of the battery. 

 

Brake Warning Light

Your brake warning light will look like a circle with an exclamation mark in the centre, surrounded by a bracket.

The brake warning light can flash when something is wrong, or otherwise vary in terms of the aforementioned green, yellow, or red colour, depending on the vehicle you drive and the seriousness of the issue.

An illuminated brake warning light can be a sign that:

• Your brake pads are worn out
• Your vehicle is experiencing hydraulic circuit failure
• Brake fluid is leaking
• Your vehicle is experiencing sensor failure

If the brake warning light stays on after you have fully released the parking brake, then you may need to have your car checked out by a garage so that they can replenish your vehicle’s brake fluid levels.

Similarly, if the light is illuminated and you find yourself having to press the brake more firmly, then you should stop driving and call for assistance.

 

 

DPF Warning Light

In a diesel car, a DPF diesel particulate filter warning light can be solid or flashing, and looks like a box with holes in it.

When the light shines yellow, this can tell you that the soot levels in your car are increasing. A flashing light, however, can mean that the soot levels are approaching full capacity and your DPF may be blocked.

You should aim to do something when you first notice the yellow warning light, as your vehicle will enter ‘limp home’ mode when the DPF is 70% full of soot.

Take your car for a drive when you first notice the warning light is lit up so that you can trigger the regeneration process.

If the warning light has been there for a while, then a drive may not be the best idea - you should book in for a professional DPF clean instead.

 

 

Electronic Stability Programme (ESP) Warning Light

The electronic stability programme helps to keep your car on the road, and looks like a car with two skid marks, against the backdrop of a triangle.

If your vehicle loses traction when driving over slippery terrain, then this can activate the ESP warning light.

However, if the light comes on and stays on whilst you are driving on normal road surfaces, then there could be any number of issues.

Best to book in with a garage so that they can find out what is causing the problem. 

 

Engine Management Light

The engine management light looks like an engine block - though a ‘check engine’ message may also appear in some vehicles.

If this light is on, this means that your car’s sensors have picked up an engine issue. This could relate to a blocked DPF, or oxygen sensor failure.

Likewise, any issues with the mass airflow sensor will likely cause the engine management light to turn on.

Problems with your vehicle’s spark plugs or a loose dipstick can also trigger this light.

The engine management light will not reset itself without the help of a qualified mechanic - and you will need to make sure your engine management light is working in advance of your next MOT. 

 

 

Engine Temperature Warning Light

An engine temperature warning light can look like a thermometer resting on two waves.

When this light shines, it is usually a sign that your engine is overheating or that there is a problem with the coolant.

If you notice this light comes on whilst driving - particularly if the light is red - you should pull over as soon as it is safe to do so.

If after letting your car cool down for at least 30 minutes, the light still comes on when you next restart your car, then you will need to have your car checked out at a garage.

Driving a vehicle with an overheating engine is not advisable, so you should call for assistance right away.

 

 

Glow Plug Warning Light

The glow plug warning light in a diesel car looks like a swirling line, and can turn on if the engine's glow plugs are still warming up - particularly in colder weather.

You should not try and drive until after this light has gone out, which should take about 10 seconds or until the engine has warmed up.

A flashing glow plug light can suggest that a glow plug has worn out - your car probably won't start if this is the case.

If you notice the light begins to flash whilst driving, you willl likely experience a loss of power and need to pull over and call a breakdown service.

 

Oil Warning Light

The oil warning light looks like an old-fashioned oil can, with a drop of oil spilling from the spout.

Depending on your vehicle, a red or flashing light can indicate that action urgently needs to be taken.

An illuminated oil warning light may shine if your oil levels are low - this can do damage to the engine when there is not the appropriate level of lubrication needed to keep it functioning safely.

This can even cause the engine to overheat, which is never a good thing.

If you suspect that your engine may be overheating, then you should stop driving and call for a mechanic to help you.

The light could also be the result of an electrical or wiring problem impacting the oil pressure gauge.

A clogged oil filter can likewise affect oil pressure.

 

 

Rear Fog Warning Light

The rear fog warning light looks like a squiggly line scored by three straight lines, and a half circle.

You may recently have driven through fog, and this light can tell you if you have forgotten to turn off your foglights.

Remember and turn your foglights off when you aren't using them, so that you don't let the bulbs blow prematurely.

If your foglights aren't working as they should, then you should book in for a diagnostic check so that a garage can find out why. 

 

Tyre Pressure Warning Light

If your tyre pressure warning light comes on, this can be a sign that your tyre pressure is too low. The symbol for this light looks like a horseshoe, and has an exclamation mark at its centre. 

Both over-inflated and under-inflated tyres can spell trouble for your car, so it is important that you always have your tyres inflated to the correct level for your vehicle.

You can refer to your vehicle’s handbook if you are at all uncertain - this can also tell you the correct size of tyres your car should be fitted with.

You don’t want an unexpected tyre blowout to lead to unprecedented spending you could have otherwise avoided. 

Changes in temperature as the seasons change can cause the tyre pressure warning light to come on.

This light may also come on if there is something sharp sticking into your tyre, or if your Tyre Pressure Monitoring System (TPMS) is not working as it should. 

 

How Do I Reset a Warning Light?

When it comes to resetting the warning lights on your dashboard, sometimes turning off your vehicle and restarting the engine can turn off and reset these lights for you.

If this does not reset the lights, then you will need to take your car to a professional garage so that they can reset the warning lights for you.

A garage will also be able to check your car is working as it should when you book in for a car service, so that you can drive knowing your vehicle is functioning properly.

In some cases - as with the engine management light  - diagnostic equipment may be required to locate the source of the issue, so you will need to book in with a skilled mechanic to have the issue resolved.

 

 

We hope you have enjoyed learning about dashboard warning lights and what they mean.