Car Warning Lights Explained

Has your engine warning light popped up? Learn all about dashboard warnings and what they mean for your vehicle with Asda Money.

Car breakdown on roadside with warning marker in foreground
08 Dec 2023

It is common for cars to experience faults at any given time. In such instances, car warning lights can help in identifying potential breakdowns. Therefore, it is important to understand the various warning lights on cars that could appear on your dashboard, as this knowledge could potentially save you from trouble.

However, decoding warning lights and car problems can be challenging. This is why we have created a blog that explains everything you need to know.


What are engine warning lights?

Modern cars are high-tech and boast many sensors, which is why warning lights are installed on the dashboards. Unfortunately, not everyone knows what these lights mean, and it can be very alarming to see one appear whilst driving. Engine warning lights could come in two different colours - orange or red.

An amber engine warning light means something is not working as it should, so it's best to take your car to a garage immediately to get it checked. Red is the most serious of the two and indicates a major problem. If a red light flashes up on your dashboard, stop driving as soon as possible.


Engine Management Light

If your engine is malfunctioning, the Engine Management Light, also known as the ‘check engine’ or ‘ECU’ light, will illuminate.

The colour of the light indicates the severity of the issue. A non-flashing amber engine warning light means you can still operate your vehicle, but you should have it inspected as soon as possible. This is the least severe of the three.

A flashing orange light means there is a problem that will affect the vehicle’s performance, such as an engine misfire, and you should have it checked out immediately.

Lastly, a red light means there is a serious issue that requires you to stop driving immediately and seek assistance from your breakdown provider.

The Engine Management Light serves as a general alert, indicating that there is something wrong with your vehicle. The light is in the shape of an engine outline.

Common reasons the Engine Management Light comes on can include:

  • Loose or missing fuel cap
  • Damaged catalytic converter
  • Problems with spark plugs in a petrol car
  • Blocked diesel particulate filter



Can I drive with the Engine Management Light on?

The colour and type of EML that displays on your dashboard will show how severe the problem is. It's important to have your car checked out as soon as possible if any EML lights appear. If the red EML light comes on, it's crucial to stop driving immediately and contact your breakdown provider.

Brake Warning Light

If you notice that your Brake Warning Light comes on after releasing the handbrake or whilst driving, it could be a sign of low brake fluid, worn brake pads, or a brake fluid leak.

Brake Warning Lights can also be known as the Brake Fluid Warning Light, Parking Brake Warning Light, or Brake Pad Warning Light.

To check for a leak, park your car and press on the brake. If it sinks to the floor, there may be a leak. You can also inspect under your car for any signs of a leak. If any of these issues are present, it is important not to drive your car and to contact your breakdown cover immediately for assistance.

Can I drive with the Brake Warning Light on?

Brakes are one of the most important parts of your car, and driving with a Brake Warning Light showing as brake failure could put you and other drivers in danger.

It is wise to slow down and avoid sudden braking, then pull over and call your breakdown provider to assist you.

Power Steering Warning Light

If you notice the Power Steering Warning Light (also called the EPS Warning Light) illuminated on your car's dashboard, it is likely indicating a problem with your vehicle's power steering system.

For electric-powered systems, it could be as easy as turning your car on and off and the light will disappear. However, in hydraulic systems, the light could indicate a leak. To ensure your safety, locate a secure place to stop, turn off your vehicle, wait for 30 seconds, and then restart it. If the light reappears after this, it's crucial to get your car checked out by a mechanic as soon as possible.

One of the most common reasons for the EPS light to appear is a leak in the hydraulic system causing low fluid levels.

Can I drive with the Power Steering Warning Light on?

Although you can still drive your vehicle with the EPS light on, it is advised to take extra caution if your power steering malfunctions. Driving with faulty power steering can make manoeuvring your car difficult and potentially unsafe.

Airbag Warning Light

A red Supplemental Restraint System (SRS) Warning Light, also referred to as the Airbag Warning Light, indicates a malfunction in one or more components of the airbag safety system. It could indicate that one or more of the airbags won’t inflate in a collision.

Deactivated airbags are something to get checked out as they could cause a significant safety issue. You should drive to your local garage immediately.

Can I still drive with the airbag warning light on?

If there are any problems with your airbag system, it is crucial to have it examined right away. Failing to do so could result in the airbags deploying unexpectedly, leading to an accident, or failing to deploy and protect you in the event of a collision.

Engine Temperature Warning Light

If your vehicle’s engine is overheating, the engine temperature warning light will turn on. If the light appears red, you must stop driving right away. This could indicate that your car is low on coolant, which may lead to irreversible damage to your vehicle.

Common causes of this light appearing are.

  • Low coolant levels
  • A leak in the system
  • OR a larger problem like head gasket failure which severely damages your engine.

Can I drive with the engine temperature light on?

Driving with the engine temperature light on can be dangerous, and should be avoided completely if the light is red. Your engine is at risk of welding itself together if there isn’t enough coolant to cool it down, which would cause irreversible damage. The best thing to do if the temperature light comes on while you’re driving is to pull over, switch off the engine, and wait for it to cool down completely before topping up the coolant tank under the bonnet as required.

While you’re under the hood, it’s worth having a look to see if there are any obvious leaks, but if the light is still on after you’ve topped up the coolant then call your breakdown provider to help you with the issue. You could let your car cool down, but you then run the risk of it happening again or your engine cutting out completely. It is safest to get professional assistance as the engine overheating can cause priceless damage to your vehicle.

Diesel Particulate Filter Warning Light

The DPF Warning Light appears when there is a problem with the exhaust particulate filter on a diesel car. The role of the exhaust particulate filter is to remove harmful soot from exhaust gases to reduce emissions.

Diesel particulate filters are something that became mandatory in diesel vehicles in 2009 to help reduce emissions, although some models did have a DPF prior to this. They need “regenerating” to prevent being blocked.

If DPF regeneration cannot be completed, driving with a blocked filter can cause serious damage to your car. The filters can be expensive to replace so it is wise to get your car looked at as soon as possible.

Can I drive with the DPF warning light on?

A blocked filter causes toxic black smoke to be released every time you accelerate, among other serious damage. It is essential to get your car to the mechanic as it can be costly to replace a filter, but it can also cause further damage to your car. Some vehicles’ DPF warning lights will ask you to continue driving to ensure the regeneration of the DPF completes, consulting your handbook could assist you with this.


Coolant Level Warning Light

The most common reason for the Coolant Level Warning Light illuminating is simply because the coolant levels are too low. The light will usually act as an alert to remind you to top up your coolant, but it could also be alerting you of a more serious issue such as a leak.

If your Coolant Warning Light pops up, you should wait for your car to cool down and then top up your coolant. If the light still stays on you should visit your local garage as there could be a bigger problem.

Can I drive with the coolant warning light on?

If your coolant level is low, it is possible to operate your car for a short period, but it is essential to refill the coolant. However, if the level is below the minimum requirement due to a coolant leak it is strongly advised not to attempt to start the engine and to contact your breakdown provider promptly.

Oil Warning Light

If you find the Oil Warning Light illuminated on your dash, it is important to act quickly. The light either means that your oil level is low, or the oil temperature is too high.

Your engine oil helps lubricate your engine and helps everything run smoothly. If the oil is not lubricating the engine properly, this can lead to irreplaceable damage to your car.

Can I drive with an oil warning light on?

You should stop driving straight away if your Oil Warning Light comes on as you may have run out of oil, continuing to drive could cause your engine to seize up, putting you and other road users at great risk. Check for any obvious leaks under the car and top up your oil levels (if you can, and if they need it). If the light goes off, you should be okay to carry on with your journey, however, if your oil levels are fine then your oil pump may be faulty, and you’ll need to call for recovery.

Low Tyre Pressure Warning Light

Many modern vehicles are fitted with tyre pressure monitoring sensors which alert you when the pressure changes. This can happen over time or be because of a puncture.

This light acts as a warning rather than a command, so you don’t need to pull over instantly, but it is advised to check your tyre pressures match the guidance in your car’s handbook as soon as you can.

Many petrol stations and supermarkets have air compressors which will allow you to inflate your tyres.

Can I drive my car with the tyre pressure light on?

Although you can still drive with the Low Tyre Pressure warning, leaving your tyres with low pressure for too long can cause safety issues. It is important to get them inflated to the level specified in your car manual as soon as possible.

Battery Warning Light

If your Battery Warning Light comes on, this indicates that your battery is not charging correctly.

Some common reasons for this light appearing are.

  • A worn-out or damaged battery
  • Charging system malfunction
  • An issue with your car’s electrical system
  • Bad electrical connection
  • Damaged cabling
  • Faulty alternator or battery

Can I still drive with a low-battery warning light?

Your car will carry on running until your battery dies, however, when this happens nothing will work so it is essential to get to the garage as soon as possible to prevent this as there is a potential for engine to cut out and won’t restart. This could leave you in an unsafe location, proceed to garage if safe to do so.

Anti-Lock Braking System (ABS) Warning Light

The Anti-lock Braking System is a safety feature in cars that prevents the wheels from locking up during hard braking. This system helps the driver maintain control of the vehicle and avoid skidding or sliding on the road.

ABS works by detecting when a wheel is about to lock up and releasing and reapplying the brakes rapidly to prevent it from happening. This allows the driver to brake hard while still being able to steer the vehicle.

ABS is an important safety feature that can help prevent accidents on the road. If the ABS Warning Light comes on your dashboard it means the antilock system has been deactivated due to a malfunction which leaves you with no assisted braking.

Can I drive with the ABS warning light on?

If your ABS warning light comes on solely by itself, you are safe to drive to your location. You just need to be cautious and keep a good distance away from cars. If the ABS light comes on and your brakes aren’t working, or it comes on alongside the Brake System Warning Light then your brake system could be failing. You should stop immediately and call your breakdown cover.

Electronic Stability Problem Warning Light

Electronic Stability Problem (Electronic Stability Control) Light indicates an issue with traction control. When the ESP system flashes, it indicates that it is taking action, such as when driving on a slippery road. However, if the light is still illuminated, it indicates that the ESP system is malfunctioning.

If the ESP system has been deactivated, the ESP warning light may illuminate with the word 'OFF'. This could have happened accidentally, so it's worth checking if you turned it off. The system can be reactivated once it's been turned back on.

Will my car drive with the ESP warning light on?

Try restarting your car, if the light stays on after restarting take your car to the garage as the ESP is an important safety feature and will need looking at.

Brake Pad Warning Light

If the brake pad warning light shows up, it means a sensor has detected your brake pads have worn too thin.

The more worn your brake pads get, the harder it will be to stop. This puts you and other road users at risk, so it is important to get the issue sorted.

Can I drive with the Brake Pad Light on?

The sensor will alert you before your brake pads become dangerously thin, however, it is important to get them replaced as soon as you can to avoid any safety issues.

How to turn off an engine warning light

Car dashboard warning lights appear when there is a problem that must be addressed promptly to avoid additional damage to your vehicle and ensure safety.

Occasionally, even after the issue has been resolved, the light may remain on. In such situations, you may need to reset your onboard computer. This can be done by disconnecting your battery for circa 30 mins and then turning your car on and off.

Alternatively, driving your car for a while may cause the light to turn off on its own. If the issue persists, a mechanic can reset your computer and resolve the problem for you.

Top Car Warning Light FAQs:

What are the worst warning lights in a car?

The check engine, ABS and Oil warning lights are some of the more serious warning lights for cars, as these could indicate a serious fault and if ignored could result in irreparable damage to your vehicle or an inability to stop the vehicle safely.

Can you drive with the engine warning light on?

It’s not recommended to drive with an engine warning light on as it could lead to a breakdown or other issues. However, as explained, the colour of the warning light helps show the severity and what your next steps should be. If in doubt, visit your local garage to double-check the warning light.

ASDA Money is a trading name of Asda Financial Services Ltd and Asda Stores Ltd which for Breakdown Cover are Introducer Appointed Representatives of Liverpool Victoria Insurance Company Limited.

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