Car warning lights – why they matter
Your car’s dashboard is like an aeroplane cockpit: it is full of dials, car indicators and warning lights that help you understand what is happening to your vehicle. While some of these symbols are quite simple, others can be a bit confusing. This guide will outline some of the most common warning lights you might encounter and explain their meaning! It will enable you to address any issues indicated by the lights, helping you to maintain your vehicle’s performance and safety.
Before driving an unfamiliar or new vehicle, it is important to be informed about its particular controls, specifications, and settings, including the warning lights on the dashboard. Although most of these lights and notifications are standardised among different vehicle makes and models, it is better to read the owner’s manual first if any unfamiliar or unclear signals are noticed.
Car warning lights – the same as traffic lights
Car warning lights are the same as traffic lights: red, yellow and green. The colour also indicates the degree of attention or warning to the driver. In general, green lights give information, yellow lights warn, and red lights force the driver to stop. Some cars also have blue car warning lights in the dashboard (a system in use, such as high beam headlights) or white car warning lights (airbags activated or deactivated, front fog lights switched on).
Green: the system is working properly or is in use;
Yellow: something is not working properly: pay particular attention and check as soon as possible;
Red: a serious and potentially dangerous problem is raised that requires immediate attention – stop driving immediately in a safe place.
Flashing warning lights inform the driver of an urgent issue.
The Check Engine Warning Light
The check engine warning light is one of the most common warning lights you’ll see on your dashboard. In some cars, the check engine warning light may be red instead of yellow or orange or replaced by the words “CHECK ENGINE”.
The check engine warning light is the most feared warning light for drivers and may come on in two ways:
– If the light is steady, you must immediately make an appointment with a trusted mechanic. They can use an appropriate self-diagnosis tester to identify the problem that caused the light to come on.
– If the light comes on intermittently, there could be a problem with the catalytic converter.
This type of warning requires more attention. The warning light can indicate various malfunctions related to the injection system, exhaust system, fuel supply, or accelerator pedal sensor. Although it is possible to drive with the engine warning light on, avoiding driving for a prolonged period or subjecting the car to excessive strain is advisable. If you must drive, it is better to choose a route that is free of inclines or hills. Ultimately, addressing the problem as soon as possible is best to avoid further damage and more expensive repairs.
The Engine Temperature Warning Light
The engine temperature warning light indicates the car’s engine is overheating, which may lead to significant engine damage. It means your cooling system is malfunctioning, and the engine cannot cool properly.
Stop the vehicle as soon as possible in a safe place! Pay attention to this warning light because the engine could be seriously damaged if you ignore it.
Check the coolant levels, and if low, top up.
Be careful! The cooling system is pressurised. Allow the engine to cool down completely before adding more coolant.
Usually, when it lights up steadily, it indicates either a lack of coolant in the system or, in cars with a variable-flow electric water pump, a pump malfunction.
!! Warning !! Don’t start the car if the warning light remains lit after topping up the coolant. The car must be towed to a workshop.
The Engine Oil Pressure Warning Light
The engine oil pressure warning light indicates the engine’s oil pressure is low. When the engine is running, oil is pumped throughout the engine to lubricate its moving parts. If the oil pressure drops below a certain level, it can cause damage to the engine. This could be due to low oil levels, a faulty oil pump, a faulty oil pressure sensor, or an oil filter clogged by debris that could restrict oil flow.
Stop the engine immediately, and do not restart it!
It is essential, in this case, to check the oil level immediately and top up if necessary.
!! Warning !! If the oil level is correct, but the light is still there, take the vehicle to our workshop with the tow truck for a proper diagnosis and repair! Do not start the vehicle; you could irreparably damage the engine!
The Battery Charge Warning Light
When the ignition is switched on, the battery charge warning light comes on as a self-check. A permanently lit battery charging light informs you of a potential issue with your car’s charging system.
This could be due to a malfunctioning alternator, a loose or corroded battery connection, or a dying battery. Electronic parts may be damaged, the engine may not restart, engine cooling may fail, and power steering may not function.
You must stop as soon as possible in a safe place. It’s important to check your battery and charging system immediately!
The Power Steering Warning Light
The power steering warning light comes on when a problem is detected in the car’s steering system. When the system fails, and the warning light comes on, the steering may become extremely heavy, making it much more difficult to turn the car. This is a dangerous problem at high speeds when you need to change direction quickly, and the car does not respond quickly. You should not drive a car with power steering problems. Contact a repair centre as soon as possible.
The Airbag Warning Light
When the airbag warning light on your dashboard turns red, it’s not good news. It means that something’s not OK with your airbag safety system. Three things could cause the problem: the airbag system itself, the front passenger classification system (which ensures the airbag deploys safely), or the seat belt tightener (which ensures your seat belt is snug in case of a crash). Since the airbag system is a passenger safety system in the event of an accident, it is important to have the car checked as soon as possible.
The Brake Warning Light
The brake warning light comes on when the handbrake is applied. If it stays on all after you fully release the parking brake or comes on when you’re driving, it means that:
– the parking brake lever/pedal must be adjusted;
– the brake pads are worn and must be replaced;
– or the hydraulic system is defective and is probably losing pressure/fluid.
If the warning light stays on, contact a repair centre immediately to diagnose and repair the brake system. If you notice your ABS (anti-lock braking system) warning light is lit up, too, it could signal a malfunction in the braking system, resulting in no brakes working.
Don’t drive the car in these conditions!
The Coolant Level Warning Light
The coolant level warning light comes on when the coolant level gets too low, and the light reminds you to top it up. Do not ignore this warning light! Coolant is an important element for proper engine operation. An engine that is not properly cooled will overheat and become damaged.
The Dpf Warning Light
The DPF warning light is a warning light found on Diesel cars. Remember that Diesel-engined cars are made to travel long distances at high speeds and not to be used in the city, where stop-and-go traffic does not allow the DPF to regenerate. The DPF warning light usually comes on when the Diesel car fails to complete the passive regeneration(at temp>=350°C) during regular use a certain number of times, and the DPF becomes clogged, reducing the amount of air passing through. When the DPF level soot is around 40-45%, the ECU performs an active regeneration that needs temperatures around 550-600°C to burn the soot and clean the DPF. If both passive and active regeneration fails to clean the DPF, the car enters ‘limp-home mode’ and going to a workshop to do a forced dpf regeneration will be necessary. If forced regeneration also fails, the DPF needs to be removed and flushed or replaced. It is important to address DPF issues promptly, as a blocked DPF can lead to reduced engine performance, increased fuel consumption, and, ultimately, costly repairs. Other causes of the presence of the DPF warning light on the dash can be a malfunctioning sensor or a problem with the DEF system.
Below is a video about a faulty DPF sensor, the warning lights that came on because of it, and how the problem was diagnosed and solved.
The ABS warning light
The ABS warning light indicates that there’s a problem with your car’s anti-lock braking system. This system helps prevent your wheels from locking up during hard braking, and a malfunction can reduce your ability to stop quickly. If you see this warning light come on, a mechanic must check your vehicle as soon as possible.
The tyre pressure warning light
The tyre pressure warning light comes on when the tyre pressure is too low. Tyre pressure drops over time or because the tyre has punctured. Low tyre pressure can cause driving problems, so reduce speed and try to avoid sudden braking or violent steering manoeuvres. Inflate your tyres at the nearest gas station or go straight to the tyre shop for a check-up.
The Traction Control Warning Light
If your car’s wheels lose traction while driving, the traction control system assists you in maintaining control of the vehicle. The traction control warning light is typically illuminated when the system is in use, indicating that your car has briefly lost traction while navigating a sharp turn or driving on wet roads. However, the traction control light may also indicate that the system has been disabled or has an issue, so it is important to be cautious while driving when the light is on. This is especially true in adverse weather conditions such as ice or snow. Additionally, your driving style can also impact how often you rely on the traction control system. If you drive recklessly, you may need to use it more frequently.
The Brake Pad Wear Indicator Light
The brake pad wear warning light can be on new vehicles and comes on when the brake pad sensor detects excessive wear, with serious consequences for the brake system’s performance and the car’s safety. It warns you that it is time to replace your brake pads before it is too late!
The Powertrain Malfunction Warning Light
The drivetrain or powertrain warning light is an important indicator on a vehicle dashboard that alerts the driver to a potential problem with the vehicle’s powertrain. The powertrain consists of the engine, transmission, and various components that work together to transfer power to the wheels. When this warning light illuminates, it could indicate various issues, such as a malfunctioning transmission or a faulty sensor. It is important to deal promptly with any issues indicated by the drivetrain or powertrain warning light to avoid more severe issues. A certified mechanic can diagnose and fix the problem, ensuring the vehicle remains in optimal condition.
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When a car warning light, steady or flashing, red or yellow, appears on your car’s dashboard, it is essential to remain calm and not panic. Reacting calmly can help you assess the situation and take appropriate measures to avoid further damage or danger.
You should consider stopping the car immediately if, with the engine warning light, there are other lights on, such as those relating to the engine overheating, the oil level or coolant level and the exhaust gas temperature gauge. In these cases, the problem is likely particularly complex, and carrying on driving could further compromise the condition of the vehicle.
It should also be noted that a flashing or steady engine warning light does not always indicate a serious problem, and if the warning light is on, but the car seems fine, you will probably be able to drive to the first garage or nearest service centre to check what is actually causing the problem.
In conclusion, understanding the car warning lights and symbols on your car’s dashboard can help you stay safe on the road and prevent costly repairs. If you see a warning light coming on the dashboard, it’s always a good idea to have the car checked in a specialised workshop by a mechanic to prevent any further damage. And if you’re ever unsure what a symbol means, consult your Owner’s Manual for more information.