Vehicle warning indicators, what are they telling you?

These days, car dashboards feature quite a variety of warning lights. Here is a list of the most common indicators.

Typically, if the light is red it’s urgent and if it is yellow, the situation is serious but not critical. Yellow warning lights should not be ignored; they mean you should take action!

Red warning lights

This is the most important indicator. It signals that your engine is out of oil or that the oil pressure is very low. You must stop the car. All the moving metal parts of the engine must be well lubricated. If you are out of oil, they will wear quickly and heat up, which puts them at risk of becoming deformed and damaging your engine.

What to do:

Stop the car in a safe spot and turn off the engine. Check the engine oil level. If it’s low, add oil. You should always carry some in your trunk. If you don’t have any oil with you, do not drive to a garage to get some. Either call someone who can bring you the oil or call an emergency road assistance service. If the indicator light remains lit even after you’ve topped up the oil, the problem may be the oil pump. This is a serious issue and you need to have the car towed.

NB: It’s normal for this indicator to light up for a moment when you start the engine, just until the oil pressure rises, but you shouldn’t drive if the light stays on.

The battery is no longer charging. The alternator, which is like a small generator, is no longer charging the battery. Either it’s defective or the drive belt that turns the alternator is damaged. If the problem is the drive belt, the engine is in danger of overheating, as that belt also drives the engine cooling system.

What to do:

You can continue to drive for a little while on reserve battery power but not for long, as your car may not start again. Have it looked at ASAP by a mechanic. While you’re driving, keep an eye on the dashboard to see if the engine temperature warning light comes on, which indicates that the drive belt is damaged.

Your engine is overheating. This could be due to a leak in a radiator hose, in the water pump, in the radiator or in the engine itself. It may be that the drive belt which drives the pump is broken. It’s also possible that the water and antifreeze mix is too low. The engine must be cool before you add antifreeze as you risk getting burned if you open the radiator while the engine is hot. Don’t drive with an overheated engine as it could damage your engine.

NB: if it’s a leak, you’ll probably see white steam coming out of your hood.

What to do:

Don’t drive for long. Have your car looked at by a mechanic. If need be, stop driving periodically to let the engine cool down. If it’s a major leak and there is coolant spilling onto the road, have your vehicle towed.

One or the other of these symbols indicates that the handbrake (parking brake) is on or that there is a problem with the brakes. Check to see whether your handbrake is on or if it hasn’t been completely released. If that’s the case, you will be wearing out the brakes and running the risk of overheating.

If the handbrake has been released and the warning light still remains on, the problem lies elsewhere. The brake fluid level is low or the pressure is low due to a leak. Your brakes may not work. You need to have the car looked at by a mechanic right away.

What to do:

If the brakes seem to be working normally, make an appointment as soon as possible with a mechanic who can identify and repair the problem. If your brakes fail while you’re driving, pump the pedal a few times to build up brake fluid pressure. Stop as soon as you can and have your vehicle towed.

This warning light indicates that a seatbelt isn’t fastened – either yours or a passenger’s. It is often accompanied by a sound alarm reminding you to buckle up for safety.

This symbol indicates that one or more doors are not completely closed. This is a safety hazard for you and your passengers. Plus, any belongings you have in the car could wind up on the road.

This light signals a problem with the airbags. If the light remains on after you’ve started the engine, one or more of the airbags isn’t working properly. For safety’s sake, you need to look into the problem and have it repaired.

NB: There is a similar warning light indicating that the passenger side airbag has been deactivated. It may light up, for instance, when the sensors detect a young child in the front passenger seat. The word “ON” or “OFF” will appear below or beside the symbol. Some cars also have a switch so that the driver can deactivate the airbag manually when a young child is aboard. Consult your car’s owner’s manual to familiarize yourself with how everything works and ensure your children’s safety. According to Transport Canada, children under 12 should always sit in the back seat.

Yellow warning lights

This one means your oil level is low. You should add oil as soon as possible before you run out. Consult your owner’s manual to find out what type of oil you need. If your car is getting old or you drive long distances you should always carry an emergency oil supply in your trunk. Remember, if the warning light is red you need to pull over and stop the car in a safe place to avoid doing serious damage to the engine.

You’re low on gas. You can still drive a few kilometers but you’d better fill up before you run out of gas.

This warning light signals a problem with the ABS braking system. The conventional brakes are still working, but you need to have the brakes checked since ABS brakes are designed to reduce the risk of skidding in an emergency braking situation.

There’s a problem with the engine. This is frequently an electronic problem (the computer, ignition, fuel injection, sensor, emission-control system, etc.). You often see this warning light when the gas cap isn’t on correctly. Many situations can generate an error code and trigger the warning light. You can still drive the car but you need to have it looked at by a good mechanic. The experts will use a computer to analyze the error code.

NB: The older your car, the more likely it is that this warning light will appear. Your car is equipped with several sensors and they often become defective with age.

This low tire pressure warning light indicates that one or more of your tires needs air. Check the pressure. You won’t necessarily find the problem tire just by looking unless it’s nearly flat. Use a tire gauge to check the pressure in all your tires. Consult your owner’s manual or look for the sticker that is frequently found on the driver’s side door frame.

Driving on underinflated tires can cause the following problems:

Increased fuel consumption

Risk of tire overheating

Risk of a flat

Risk of skidding

Risk of damaging the tires and the wheels

You’re low on windshield washer fluid. Fill up your reservoir as soon as possible. Whenever you fill up the windshield washer fluid, buy a new jug immediately to keep in your trunk so you can always top up. It will come in handy, especially in winter.

This is your electronic stability control (ESC) warning light. When it’s on or flashing, it means that you are on a slippery road and the ESC system is working to stabilize the car. Sometimes called traction and skid control, the ESC reduces the risk of accident by performing both functions. But you still need to adjust your speed to the road conditions.

Your electronic stability control (ESC) is deactivated. There’s a switch on your dashboard that allows you to deactivate the system. You might want to do this, for instance, when you are stuck in snow or sand, or you are driving with a spare tire. In normal driving conditions, the ESC should be activated. Make sure not to deactivate the system by accidentally flipping the switch.

Other warning lights

Your low beams are on. They should only be used when you encounter oncoming traffic to avoid blinding other drivers.

Your high beams are on. They are used to help you see farther ahead.

Your fog lights are on. Lower down on the vehicle, these lights illuminate the foreground and road edges in fog conditions. Always slow down when driving in fog.

These warning symbols are universal and some are even found on motorcycles.

It’s always a good idea to refer to your owner’s manual and keep it in your glove compartment. It contains information about your specific car model. You should read it over at least once when you first get your car. And when you sell the car, leave the manual in the glove compartment; the next owner will thank you for it!



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