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Whether you’re driving an A Class, GLA, AMG, CLA or another model, the warning lights on your Mercedes-Benz's dashboard follow a traffic light colour system: Automotive Electric Cooling Pump
Modern Mercedes-Benz cars are filled with lots of sensors that monitor how each system in the car is behaving. The lights on the dashboard display what systems are in use and they also highlight when one of those systems is not working as it should.
But what do all those different symbols mean? We’ve put together this guide to help you understand what the different yellow and red warning lights on your Mercedes-Benz dashboard mean, why they come on, how urgent the problem is and what you should do when you see them.
If this red light remains on after you fully release the parking brake, or comes on when you’re driving, it may indicate that the brake fluid level is low. Unless you know how to check your brake fluid levels yourself, this will be one for the professionals.
If the ABS warning light is also illuminated this signals that the braking system has malfunctioned and your brakes may not work properly. In this case the Electronic Brake Force Distribution (EBD) warning light may also be illuminated.
You shouldn't risk it. The brakes are one of the most important safety features of your car, so it’s important to act immediately when you see this red warning light to avoid your car breaking down.
Pull over and stop as soon as it’s safe to do so - keep your speed low and avoid braking suddenly. Unless you know how to check your brake fluid levels yourself, this will be one for the professionals, so get yourself to a garage.
Don’t risk driving when your brakes are not functioning properly: call for recovery if you have a breakdown cover policy.
If you need assistance you can call the RAC on 0330 159 1111 whether you are a member or not.
When the check engine warning light is illuminated it’s often accompanied by tell-tale signs that the engine is not working properly, such as a lack of power or stuttering as you press the accelerator.
This light could indicate a number of faults, from minor issues like a broken electrical sensor to a much larger mechanical issue, like a fault with your emission control system or catalytic converter.
If the check engine light comes on you should get it checked as soon as you can, as by continuing to drive you risk causing further, potentially irreparable damage to your engine.
Use our search tool to find your nearest RAC approved garage. Or, if you have RAC Breakdown Cover, call for recovery. Additionally, ensure you are covered if you see warning lights on your trip away with our European Breakdown cover.
This warning light indicates that there’s a problem with the power steering.
For electric powered systems, this problem could be as simple to fix as rebooting a computer. Find a safe place to stop and try turning the car off and back on again after 30 seconds. If the light stays on you should take your car to get checked as soon as possible.
You can but if the power steering system fails you will notice that the car is harder to manoeuvre and you should take extra care – it could be dangerous to drive at high motorway speeds without power steering assistance.
If you have a diesel Mercedes-Benz, this light will come on if there is a problem with the exhaust particulate filter, which removes harmful soot from the exhaust gases to reduce emissions. It could indicate that the filter has become blocked with soot.
As well as releasing a plume of toxic black smoke every time you press the accelerator, driving with a blocked filter could cause more serious damage to your car. You should go to a garage to get it checked as soon as you can, as these filters can be expensive to replace.
Learn more about diesel particulate filters and how to maintain them.
Adblue® is a type of diesel exhaust fluid. If this light turns yellow it means the diesel exhaust fluid level is low, which will eventually prevent your engine from starting.
You should go to get the levels topped up as soon as you can, as once the light turns red the level has become so low, the engine won’t start again once turned off.
If you need advice on topping up your diesel exhaust fluid levels, read our guide to AdBlue®.
Coolant fluid absorbs the heat from your engine and disperses it through the radiator to prevent your engine from overheating. This yellow warning light will come on when coolant levels are running low, to remind you to top them up.
Avoid making any long journeys without sufficient coolant: you should stop and top up as soon as possible otherwise you risk causing serious damage to your car. Wait for the engine to cool down before topping up. Read our guide to checking your engine coolant.
If this light comes on often, get your car serviced to check there isn’t a leak somewhere.
This light will come on when the engine is overheating. This could mean that coolant levels are running low, perhaps due to a leak in the system, or it could be a sign of a larger problem, like a head gasket failure.
If this light is red you should stop straight away, as without enough coolant your engine could get so hot that it effectively welds itself together, causing irreparable damage.
Stop and wait until the engine has cooled off before checking the gauge on the side of the coolant tank under the bonnet, topping up as required. Read our guide to checking your engine coolant.
While you’re under the hood, have a look to see if there are any obvious leaks. If you can’t see any and the light goes off after topping up then you should be fine to continue your journey. If the light comes back on again after topping up you should get it checked out to fix the underlying problem.
An overheating engine can cut out as well. Rather than risk it, you should call for recovery if you have breakdown cover.
The oil warning light comes on when either the oil temperature gets too high or the oil level or pressure is too low. If the oil is not lubricating the engine effectively it could lead to expensive or even irreparable engine damage, so it’s important to act quickly.
When this light comes on you should stop as soon as possible and turn off the engine. Have a look for any obvious oil leaks under the car, and then check the oil levels, topping up if necessary.
If the oil levels are fine, then the oil pump may be faulty. In this case call for recovery if you have breakdown cover, as driving any further could damage the engine. Watch our video guide to checking your car’s engine oil.
While you’re under the hood, have a look to see if there are any obvious leaks. If you can’t see any and the light goes off after topping up then you should be fine to continue your journey. If the light comes back on again after topping up you should get it checked out at a garage to fix the underlying problem.
Many Mercedes-Benz cars are now fitted with tyre pressure monitoring systems that will let you know when the pressure falls. This could happen over time or it could be because of a puncture.
Yes, but you should drive with extra care and aim to top up with air at the next opportunity. Low tyre pressure can cause unsafe driving conditions so reduce your speed, and try to avoid braking suddenly or making any violent steering manoeuvres.
Most petrol stations and garages will have an air compressor you can use to check your tyre pressure. Top up the air in the tyres according to the vehicle manufacturer specification in your owner's manual.
If you have a puncture, watch our video to learn how to change a tyre in 10 simple steps.
If this light comes on when you’re driving it indicates that the battery is not charging. This could be due to a problem with your car’s electrical system and it could have several causes, such as a faulty alternator, faulty battery, bad electrical connection or damaged cabling.
Your car will run as normal until the battery is dead but once it is drained nothing in your car will work – so get to a garage quickly before you run out of juice!
If you do run out of charge, you can try to jump start it, or call for recovery if you have RAC Breakdown cover
ABS is an important safety feature that really comes into play when you need to make an abrupt stop, or in difficult driving conditions like icy roads.
If the ABS light comes on by itself you should still have normal, unassisted braking, so it's safe to continue your journey – but keep your distance, take extra care, and get it checked as soon as possible.
If it comes on with the brake warning light, it could indicate that the brake system is failing and you should stop straight away and call for recovery if you have breakdown cover.
For roadside assistance, you can call the RAC on 0330 159 1111 even if you’re not a member.
If this light comes on it means a sensor has detected your brake pads are too thin.
This warning light should come on before the brake pads become dangerously thin, so you have time to get them changed. You should replace as soon as you can though, as if they wear out completely it could be extremely dangerous.
For more information read our guide to brake pads.
Also called Electronic Stability Control (ESC), this warning light indicates a problem with traction control. If it’s flashing it means the ESP system is intervening – for example, if you’re driving on a slippery road. If the light stays on it means the ESP system is not working properly.
The ESP light will light up with the word ‘OFF’ if the system has been deactivated, in which case you may have inadvertently turned it off.
To check, try stopping and restarting the engine. If the light remains on after restarting get it checked at a garage as the ESP system is an important safety feature.
The difference is in your pocket.
*£7 a month for new, single vehicle Basic cover. Comparison based on www.theAA.com closest equivalent cover as at 03/04/24.
If you have a diesel Mercedes, this light will turn on when the engine is warming up.
Wait until the light goes off before starting your car. If this light is flashing it indicates that it’s not working properly and the glow plugs may need replacing.
Get it checked as soon as possible. A fault with the glow plugs may put the engine into safe mode to prevent any damage to the engine so you may experience a noticeable drop in performance until the problem is fixed.
When this light goes red it means that at least one element of the airbag safety system is not working correctly: either the airbag system itself; the front passenger occupant classification system (which detects the front passenger’s weight and position in order to safely deploy the airbag); or the seat belt pretensioner system, which tightens the belt in the event of a crash.
If the airbag system is not working properly, it may not go off in a crash - or in some cases it could even deploy unexpectedly and cause a crash. Either way, the airbag system is an incredibly important safety feature of your car so if this light comes on please get it checked out immediately.
BAS is a safety feature available on some Mercedes cars - also known as the PRE-SAFE® Brake - that uses a sensor to scan the road ahead, measuring the distance and relative speed of the vehicles in front, so that it can warn you - both visually and audibly - if you get too close.
It prepares the brakes for emergency braking if it senses that you’re in danger of collision, adding extra force to your brakes, and if a crash is imminent the system will automatically apply the brakes and retract the seatbelts to brace you.
If the warning light comes on it means that the system is temporarily unavailable, possibly because the sensor is either too hot or cold, or clogged with dirt.
Try waiting for the sensor to cool down/heat up, and check to see if there is any dirt or debris blocking the sensor. If the light doesn’t go off this may mean there is a bigger malfunction in the system that you need to get looked at by a professionl mobile mechanic.
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This light will come on if one of your lights needs replacing. A message on the dashboard should help you identify which light is out.
You’ll need to get this replaced as soon as you can, not least because they’re an important safety feature but also because your car won’t pass its MOT without a full set of working lights.
If the brake light is out get it fixed immediately. If you continue driving you may get pulled over the police, either for a verbal warning, a notice to get the light fixed within 14 days, or even a fine and points on your license.
Read our guide to checking your lights.
Some modern Mercedes cars use hybrid systems to reduce emissions and improve performance. This clever system can shut down the combustion engine, and instead allow the battery to power your car.
If this warning light comes on, indicating a fault with the hybrid system, stop when it’s safe to do so and try turning the car off for a few minutes to allow the computer to recalibrate. If this doesn’t clear the light you could also try checking the fuses if you know how. Otherwise, you’ll need to get a professional to take a look, as there are a number of issues that could cause this complex system to malfunction.
Depending on the severity of the problem you may not be to drive the car, and you may need roadside assistance. Note that two different warning lights could be illuminated in this situation, depending on whether or not the car can be towed safely. If the car symbol is lit up and you need recovery, the car will have to be moved on a transporter or trailer instead.
Even if you are able to continue driving you should go and get it checked out straight away - hopefully it’s a simple problem to fix, but equally it could be a sign of a larger issue.
Mercedes’ ATTENTION ASSIST® is a safety feature available on newer models that monitors your driving behaviour.
It looks at things like your speed and steering, alongside road conditions, weather and time behind the wheel - and looks out for signs that you’re getting tired.
The ATTENTION ASSIST® warning light will come if the computer assesses that drowsiness or fatigue are affecting your driving, reminding you to take a break and recharge your own batteries.
This ‘catch-all’ exclamation mark warning light will come on to warn you if there is a problem that needs your attention.
There are several reasons this light might come on but it should be accompanied by a message on the dashboard that indicates the problem.
It may simply show that you’ve left an indicator or your lights on, or it could be a reminder to refuel. Alternatively, it could be an operational problem with the automatic or hybrid drive mode you’re using. In the worst-case scenario it could warn you that the engine will not restart again once it’s turned off, in which case don’t stop: drive straight away to get it checked out.
Are you interested in purchasing some replacement car mats for your Mercedes? Be sure to check out our range over at the RAC Shop.
This can be done by opening and closing the bonnet and then turning your vehicle on and off. However, if it still remains on, you may need to disconnect and then reconnect your battery. In some cases, it may be that you will need to drive for a while for the car to reset itself.
This is unsafe and should not be attempted. Visit a garage or mobile mechanic to get it sorted. If the issue is resolved, then carry out a reset and the light should disappear.
This is also ill-advised, as it is a warning that your vehicle is not in a safe condition. If the light will not disappear, then you will need to contact a local Mercedes-Benz dealership.
Also called Electronic Stability Control, this warning light indicates a problem with traction control. If it’s flashing it means the ESP system is intervening – for example, if you’re driving on a slippery road. If the light stays on it means the ESP system is not working properly. The ESP light will light up with the word ‘OFF’ if the system has been deactivated.
*Learn more in the article above
When the yellow check engine warning light is illuminated it’s often accompanied by tell-tale signs that the engine is not working properly. This could mean several faults are happening within your vehicle. Visit a garage as soon as possible.
When this light goes red it means that at least one element of the airbag safety system is not working correctly. This is a major safety issue - visit a mechanic.
All modern Mercedes articles have the same style of car dashboard warning lights.
The triangle exclamation mark warning light will come on to let you know if there is a problem that needs your attention. There are several reasons this light might come on but it should be accompanied by a message on the dashboard that indicates the problem.
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*£7 a month for new, single vehicle Basic cover. Comparison based on www.theAA.com closest equivalent cover as at 03/04/24.
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The difference is in your pocket.
*£7 a month for new, single vehicle Basic cover. Comparison based on www.theAA.com closest equivalent cover as at 03/04/24.
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