Car indicators: a guide to symbols, colours and meanings

Are you in doubt about your car’s warning lights? Read the complete guide on the different meanings and find out how to behave in every situation Warning lights on the car’s instrument panel are essential for monitoring the status of the vehicle and ensuring safe driving. When a warning light comes on, it may simply signal the activation of a system or indicate a problem that requires immediate attention. Car warning lights are designed to provide quick and clear information on the vehicle’s status, using clearly defined colours and symbols. In this comprehensive guide, we will explain the meaning of each colour and symbol, how to interpret them correctly and how to react in each situation to keep your vehicle in perfect condition. We will also explain how these behave in the presence of an LPG system.   Car Warning Lights: Colors and Meanings Car warning lights are designed to quickly communicate the status of your vehicle, allowing you to easily spot any anomalies or confirmations that certain systems are working. Each warning light has a specific color, which represents a different level of severity and helps you determine whether it is a simple warning or a problem that requires immediate attention. Below, we will examine the different warning light colors in detail, explaining what they indicate and how you should behave in each situation to keep your vehicle in safe conditions and prevent breakdowns or malfunctions.   Red lights: serious problems and immediate danger Red lights are the most important, as they indicate a serious problem that could compromise vehicle safety or cause serious engine damage. If a red warning light comes on, it is essential to understand the nature of the problem and take prompt action. Oil pressure warning light (1) Symbol: bottle of oil with a drop falling out, often accompanied by the word ‘OIL’ or a similar sign. When this warning light comes on, it means that the oil pressure in the engine is too low. Move to a safe area and check the oil level, adding oil if necessary. If the level is correct but the warning light stays on, there may be a problem with the pump. Brake warning light (2) Symbol: circle with an exclamation mark or the letter “P” in the centre, surrounded by brackets or a circle. When this warning light comes on with the parking brake disengaged, it could indicate a problem with the brake system, such as a brake fluid leak or brake servo failure. Pull over to a safe place and check the brake fluid level. If the problem persists, contact a mechanic. Cooling system warning light (3) Symbol: thermometer immersed in a wavy fluid. When this warning light comes on, it means that the engine is overheating. To solve the problem, switch off the engine and let it cool down. Check the coolant level and add coolant if necessary. If the level is correct but the warning light stays on, there may be a problem with the water pump or thermostat. In this case, stop when you can and call a mechanic. If the engine emits smoke, wait for it to cool down before opening the bonnet. Battery warning light (4) Symbol: battery with “+” and “-” sign. When this light comes on, it indicates a problem with the power supply or alternator. It may indicate a low battery or a fault with the charging system. If the warning light comes on while you are moving, have the electrical system checked to avoid any inconvenience while driving. Airbag warning light (5) Symbol: Figure of a seated person with a circle in front (representing the airbag). When this warning light comes on, it indicates a malfunction in the airbag system. This could mean that the airbags will not deploy in the event of an accident or, conversely, that they could deploy accidentally. It is advisable to take the car to a workshop as soon as possible to have the safety system checked. Door open indicator light (6) Symbol: Car seen from above with doors open. When this symbol illuminates, it means that one or more doors are not closed properly. Before driving, check that all doors (including the boot) are securely closed and that this light is off. Seatbelt warning light (7) Symbol: Figure of a seated person with a seatbelt across the chest. When this symbol illuminates, it means that the driver or one of the passengers has not fastened the seat belt correctly. Make sure that all belts are fastened before driving. In some car models, the warning light is accompanied by an acoustic signal that stops only after the seat belt is fastened.   Orange or yellow warning lights: warnings and malfunctions Orange or yellow warning lights indicate a warning or malfunction that does not require immediate action, but should be resolved as soon as possible. They generally indicate problems with the engine, control systems or safety. In many cases, it is possible to continue driving with caution, but it is always best to have the vehicle checked as soon as possible to avoid more serious damage. Engine failure warning light (Check Engine) (1) Symbol: stylised engine or “CHECK ENGINE” lettering. When this light comes on, it indicates a general problem with the engine or electronic management system. The causes could be anything from a power supply problem to a sensor failure. It may also come on in the event of abnormal combustion or catalyser malfunction. If the warning light is steady, you can continue driving safely, but it is recommended to have the vehicle checked as soon as possible to prevent the problem from worsening. If the warning light is flashing, stop somewhere safe as it could indicate a serious combustion or engine problem. If in doubt, it is best to contact a mechanic. When the car is in LPG mode, the car’s original electronic control unit continues to work as if the LPG system was not present, adopting a master&slave architecture. In this architecture, the master (the petrol engine control unit) controls the vehicle and all other systems (the slaves, which in this case are those of the LPG system) are passive, waiting for instructions from the master. For example, it is the petrol ECU that manages the correct supply for the engine. Consequently, when the check engine light comes on, the problem is generally related to the petrol supply, and must be diagnosed using the appropriate tools. The tools required for accurate diagnosis are available from authorised BRC workshops, which have specific technology for the LPG system. Pollution control system warning light (2) Symbol: silhouette of an engine or exhaust pipe. When this warning light comes on, it indicates a malfunction in the emission control system. This could be a problem with the catalytic converter, lambda sensor or particulate filter (DPF). If the light is steady, you can continue driving, but it is advisable to visit a workshop for a thorough diagnosis. If the warning light is flashing, it may indicate a more serious problem that can cause damage to the engine or exhaust system and you should contact a mechanic. Tyre pressure warning light (3) Symbol: exclamation mark inside a stylised section of tyre. When this warning light comes on, it indicates a loss of pressure in one or more tyres. There could be a puncture or simply too little pressure in the tyres. Stop in a safe place and check the pressure of all tyres. Inflate the deflated ones according to the instructions in the owner’s manual. If the warning light stays on or comes on again after inflating, there may be a puncture or sensor problem. Glow plug indicator light (diesel engines) (4) Symbol: horizontal spiral or glow wire. When this light comes on, it indicates that the glow plugs are heating up to start the engine. If it remains lit after starting, it may indicate a malfunction in the glow plugs or preheating system. If the light remains steady after starting, you can continue driving, but it is advisable to have the preheating system checked as soon as possible. If it flashes, stop as soon as possible and contact a mechanic. Rear fog lamp (5) Symbol: A stylised headlamp, facing to the right, with horizontal lines and a wavy line running through them. When this light comes on, it indicates that the rear fog lights are active. These lights are used to improve the visibility of those following you, especially in fog or adverse weather conditions. Low fuel level warning light (6) Symbol: stylised fuel pump. When this warning light comes on, it indicates that the fuel level is low and that refuelling is necessary. Drive to the nearest service station and fill up with petrol to rectify the problem. If the warning light stays on, there may be a problem with the tank sensor. If your car is fitted with an LPG system, you may find that when running on gas you do not need to take into account the range and fuel consumption indications given by the car’s on-board computer and petrol level indicator. The actual petrol level may only be visible when the vehicle is started. After switching to gas, there may be an apparent drop in the petrol level proportional to the mileage driven. After the vehicle has been switched off and only after a few minutes have elapsed since the vehicle was started, the actual petrol level can again be detected. ABS (anti-lock brake system) warning light (7) Symbol: Circle with the word “ABS” in the centre. When this warning light illuminates, it indicates a malfunction in the ABS system. The conventional brake system will continue to function, but the anti-lock system may not be operational. ABS prevents the wheels from locking during braking, improving vehicle control. It is still possible to continue driving, but without this functionality. It is therefore advisable to have the system checked as soon as possible to avoid risks in the event of emergency braking. Brake pad wear warning light (8) Symbol: circle with two dotted lines on either side. When this light comes on, it indicates that the brake pads are worn and need replacing. You can continue to drive with caution, but it is advisable to have the brake pads replaced as soon as possible to avoid damage to the discs and loss of braking effectiveness.   Green warning lights: vehicle information and status Green warning lights are indicators that provide information on the operating status of the vehicle, without indicating any problems or malfunctions. They are indications of active functions or systems operating normally. These lights do not require any immediate action and do not indicate any problems, but are useful for keeping the driver informed of the vehicle’s condition. Indicator light on (1) Symbol: a stylised light bulb or the word “ON”. When this light comes on, it indicates that the vehicle’s lights, such as headlights or sidelights, are on. It is a useful reminder that the lights remain on when the engine is switched off. If they are not needed, turn them off to avoid unnecessary battery drain. Direction indicator light (arrows) (2) Symbol: an arrow pointing to the left or right. When this light comes on, it means that the direction indicator (arrows) is activated and functioning properly. Check that the direction indicator is working as intended. If the indicator light flashes rapidly or does not go out, there may be a problem with the indicator bulb. Low beam warning light (3) Symbol: A stylised headlight with horizontal lines simulating the beam. When this warning light comes on, it indicates that the low beam headlights are on. These headlamps are used to illuminate the road without blinding other drivers, especially in conditions of reduced visibility such as at dusk or on cloudy days. Front fog lamp (4) Symbol: a stylised headlamp, facing to the left, with horizontal lines and a wavy line running through them. When this warning light comes on, it indicates that the front fog lights are on. These lights are used to improve visibility in dense fog or heavy rain, without blinding other vehicles. Cruise control warning light (5) Symbol: a steering wheel or car icon with a circular arrow. When this light comes on, it indicates that cruise control is active. Make sure that cruise control has been activated intentionally. If you want to deactivate it, simply press the “OFF” button or switch off the engine. Start-Stop system warning light (6) Symbol: a circle with a power icon (similar to the engine start button). When this light comes on, it indicates that the Start-Stop system is active. This system automatically switches off the vehicle’s engine when it stops to save fuel and reduce emissions. If the warning light is on and you do not wish to use the system, you can deactivate it by pressing the appropriate button. Otherwise, you can continue driving normally. If the warning light comes on and does not go out when the engine should restart, there may be a problem with the system. Eco warning light (7) Symbol: “ECO” lettering or a stylised leaf. In some vehicles, it may also be represented by a car icon with a circular arrow. When this indicator light comes on, it means that the vehicle is operating in eco mode, a setting that optimises fuel consumption, reduces emissions and improves vehicle efficiency. LPG gas switch indicator light (8) Symbol: A stylised LPG pump or gas cylinder or a fuel symbol with the LPG indication. In some vehicles, especially on those developed directly by the manufacturers, it may be represented by an icon indicating a change between fuels, such as an arrow suggesting a change between petrol and LPG. This indicator light is usually green, but in some cases it can be orange.   On cars converted to After-Market, the LPG operating status indication is displayed on the LPG switch. The lights on the gas switch indicate whether the car is running in petrol or LPG mode and provide an indication of the amount of LPG in the tank. For any other error messages indicated by the LPG switch, please refer to the owner’s manual. If in doubt or for complex problems, it is always advisable to contact an authorised BRC workshop for professional diagnosis and possible assistance.   Blue warning lights: status signals Blue warning lights are among the least common and generally indicate that a vehicle system or function is activated. Unlike red or yellow lights, blue lights do not signal a problem, but simply provide information on the operating status of certain devices, such as headlights or engine temperature. High beam warning light (1) Symbol: a stylised headlight with horizontal light lines pointing to the left. When this symbol illuminates, it indicates that the high-beam headlights are switched on. This indicator light is blue to easily distinguish high beam from low beam or position lights. It is important to remember to switch off the high beam when passing other vehicles so as not to cause visibility problems for other motorists. Coolant temperature warning light (cold) (2) Symbol: a stylised thermometer with waves underneath. When this light comes on, it means that the engine is still cold and has not reached optimum operating temperature. It is advisable to drive carefully until the engine reaches the ideal temperature. If the warning light stays on for a long time or starts flashing, there may be a problem with the cooling system. In that case, have the vehicle checked by a mechanic.   White warning lights: general information White warning lights provide general information on vehicle status or driving settings. They suggest an action or confirmation regarding the operation of a system. These warning lights serve to guide the driver and facilitate vehicle operation. Automatic parking system warning light (3) Symbol: the letter “P” with a small steering wheel or a curved arrow. When this indicator light comes on, it indicates that the automatic parking system is ready for use or is being activated. Driving mode indicator light (4) Symbol: a car icon with the letters ‘ECO’, ‘SPORT’ or ‘COMFORT’. When this indicator lamp lights up, it indicates that a specific driving mode has been selected, such as Eco for fuel economy or Sport for a more responsive drive.   Conclusions In conclusion, understanding the meaning of the car’s warning lights is essential for safe driving and keeping the vehicle in perfect condition. Each warning light has a precise message that, if interpreted correctly, will help you prevent breakdowns or serious problems. Taking care of your vehicle is essential to ensure safety, efficiency and longevity.