Car warning lights: everything you need to know (2024)

It can be alarming when you’re driving and your dashboard flashes with a light you haven’t seen before. You can’t always pull over immediately and sometimes you won’t be close to a garage.

So, how do you know which lights are the ones you shouldn’t avoid? Moneybarn has put together a guide to the dashboard warning lights you can’t afford to ignore.

It can be alarming when you’re driving and your dashboard flashes with a light you haven’t seen before. You can’t always pull over immediately and sometimes you won’t be close to a garage.

So, how do you know which lights are the ones you shouldn’t avoid? Moneybarn has put together a guide to the dashboard warning lights you can’t afford to ignore.

If either your anti-lock brake system (ABS) or brake fluid warning lights appear, it means there’s a fault with your brakes.

This could be your brake pads being low on material, a broken sensor or – in the case of the ABS light – it means the system which stops your wheels from locking is broken, which could mean your vehicle skids across the road when you try to use your brakes.

It’s also important to keep your tyres inflated properly to help with braking and is a key component of staying safe whilst driving.

Fully working brakes are crucial for vehicle safety, so don’t mess around when it comes to a potential fault. Stop your vehicle safely as soon as the light appears and call a mechanic straight away.

If either your anti-lock brake system (ABS) or brake fluid warning lights appear, it means there’s a fault with your brakes.

This could be your brake pads being low on material, a broken sensor or – in the case of the ABS light – it means the system which stops your wheels from locking is broken, which could mean your vehicle skids across the road when you try to use your brakes.

It’s also important to keep your tyres inflated properly to help with braking and is a key component of staying safe whilst driving.

Fully working brakes are crucial for vehicle safety, so don’t mess around when it comes to a potential fault. Stop your vehicle safely as soon as the light appears and call a mechanic straight away.

Unlike other warning lights, the engine control unit (ECU) light doesn’t signal a specific fault – it simply tells you there’s a problem with the engine.

Most ECU light systems use amber and red coding to signify the degree of the fault. If the light’s amber it usually means a fault with the exhaust emissions and you should be able to drive home safely but, make sure to book in with a mechanic as soon as possible.

Amber lighting with additional lines means you should drive cautiously to the nearest garage, while red lights mean a serious fault, so stop the vehicle and call a breakdown service immediately.

Unlike other warning lights, the engine control unit (ECU) light doesn’t signal a specific fault – it simply tells you there’s a problem with the engine.

Most ECU light systems use amber and red coding to signify the degree of the fault. If the light’s amber it usually means a fault with the exhaust emissions and you should be able to drive home safely but, make sure to book in with a mechanic as soon as possible.

Amber lighting with additional lines means you should drive cautiously to the nearest garage, while red lights mean a serious fault, so stop the vehicle and call a breakdown service immediately.

In diesel vehicles, soot can build up in the exhaust and cause a clog. Vehicles will have a built-in ‘regenerator’ which burns the soot and removes the build-up, but this only happens when driving at certain speeds.

If you fail to remove the soot build-up in your exhaust, it’ll reduce the airflow and start to impact your vehicle’s performance.

If the diesel particulate filter warning light shows on your dashboard, continue driving safely and find the nearest fast road and drive for around ten minutes at 40 mph or higher (on suitable road types) to trigger the regeneration system.

In diesel vehicles, soot can build up in the exhaust and cause a clog. Vehicles will have a built-in ‘regenerator’ which burns the soot and removes the build-up, but this only happens when driving at certain speeds.

If you fail to remove the soot build-up in your exhaust, it’ll reduce the airflow and start to impact your vehicle’s performance.

If the diesel particulate filter warning light shows on your dashboard, continue driving safely and find the nearest fast road and drive for around ten minutes at 40 mph or higher (on suitable road types) to trigger the regeneration system.

Your airbag warning light will come on if there’s a problem with your airbag system or possibly your seatbelt mechanism.

This will usually mean your airbag needs resetting or that there’s a problem with the battery or the wiring in the airbag system.

As soon as you see the light turn on, either pull over safely or drive cautiously to a garage if there’s one nearby.

If you’re involved in a crash while the airbag warning light is on, your airbags won’t deploy for you or your passenger, which could prove fatal, so it’s not recommended you drive while it’s on.

Your airbag warning light will come on if there’s a problem with your airbag system or possibly your seatbelt mechanism.

This will usually mean your airbag needs resetting or that there’s a problem with the battery or the wiring in the airbag system.

As soon as you see the light turn on, either pull over safely or drive cautiously to a garage if there’s one nearby.

If you’re involved in a crash while the airbag warning light is on, your airbags won’t deploy for you or your passenger, which could prove fatal, so it’s not recommended you drive while it’s on.

The battery warning light will appear whenever you turn on your vehicle. If it stays on while the engine is running and you’re driving around, though, it means there’s a problem with the charging system.

Problems with your vehicles battery could be down to a number of issues – like a loose cable – but it could mean you eventually run out of power and come to a halt while driving. It could also mean your vehicle overheats or your power steering system stops working, all of which could be dangerous.

The battery warning light will appear whenever you turn on your vehicle. If it stays on while the engine is running and you’re driving around, though, it means there’s a problem with the charging system.

Problems with your vehicles battery could be down to a number of issues – like a loose cable – but it could mean you eventually run out of power and come to a halt while driving. It could also mean your vehicle overheats or your power steering system stops working, all of which could be dangerous.

The oil pressure light coming on can mean anything, from being low on oil to there being a fault with the vehicle’s engine.

Driving with an oil fault can cause havoc with your vehicle’s engine and even break the motor. So, if the light comes on while you’re driving, pull over and stop the vehicle as soon as possible and call a mechanic.

The oil pressure light coming on can mean anything, from being low on oil to there being a fault with the vehicle’s engine.

Driving with an oil fault can cause havoc with your vehicle’s engine and even break the motor. So, if the light comes on while you’re driving, pull over and stop the vehicle as soon as possible and call a mechanic.