What Do All Your Dashboard Lights Mean?
  • Buying Guides

What Do All Your Dashboard Lights Mean?

By Shawn Furman | October 20, 2021

Modern cars and trucks today often have tons of warning lights to indicate anything from a friendly service reminder to a much more serious problem.

To make it worse, not every dashboard warning light is universal. Most of the important lights like the check engine light, the tire pressure warning light, and the airbag light are almost universally used and recognized, but there may even be slight variations in some of these from vehicle to vehicle.

The best glimpse of the dashboard warning lights is when the engine starts. Several of these warning lights will illuminate under normal conditions so you know they are working, but it is also normal for them to all go out after a few seconds. If one or more lights stay on, there may be a problem. You should always refer to your owner’s manual if you are unsure of what a dashboard warning light means.

Check Engine Light:

The check engine light is one of the most ominous warning lights on the dashboard and one that is the most universally recognized. Though there can be slight variations in how the check engine light appears, it is usually a yellow or orange light and usually looks like the outline of an engine, sometimes with the actual words “check engine” within it.

For as useful and recognizable as the check engine light is, it is also one of the most frustrating since it can indicate anything from a loose gas cap to a more serious issue like engine knocking. It is designed as a “catch-all” light to detect any issue within the engine and its related systems, and it can often overlap with other more specific warning lights.

If your check engine light comes on and nothing appears to be wrong, it is best to pull over or get to a close shop with an OBD II reader that can diagnose the exact issue. To avoid making a potentially serious problem worse, drive as little as possible before having the issue diagnosed, and do not drive your car with the check engine light flashing.

Oil Pressure Warning Light:

The oil pressure warning light is usually red and looks like an oil can with a drip. It indicates an issue with the oiling system, whether that be a failed oil pump, insufficient oil circulation causing engine overheating, low oil levels within the vehicle, low engine oil pressure, the incorrect type of oil added to the vehicle, or even too much oil added.

Insufficient or incorrect oil pressure within your engine can be one of the worst-case scenarios for your vehicle’s health since your engine relies on oil to function well. If this dashboard warning light comes on, you should diagnose and address the issue as soon as you can. Some vehicles also have an oil life indicator or oil change reminder.

Tire Pressure Warning Light:

The tire pressure warning light is self-explanatory and universally known, probably more for being a pain in the colder winter months than being a true emergency. It looks like a circle with a flat bottom and an exclamation point inside. It indicates low tire pressure, usually when there is a 25% drop in the required pressure within one or more tires.

In addition to the tire pressure light, your vehicle may have a separate tire pressure monitoring system light that comes on when the system needs to be reset or if there is a malfunction in the system that indicates low tire pressure. This light often just has the letters TPMS illuminated. In some vehicles, the tire pressure light can indicate either a system problem or low tire pressure.

Airbag Warning Light:

The airbag warning light is a simple one, but one that should not be ignored. It looks like a person sitting in a seat with a seatbelt and the airbag being deployed, and it usually indicates a fault in the supplemental restraint system – or SRS – in the vehicle. Since a malfunction in the SRS system can prevent the airbag from deploying in the event of a crash, you should not drive the vehicle when the airbag light is on.

ABS Warning Light:

ABS stands for the anti-lock brake system, and it prevents the brakes from locking up during hard braking, allowing you to stop and steer the vehicle in low traction situations. A bad wheel speed sensor, low brake fluid levels, and a faulty ABS module can all be to blame.

When the ABS system warning light comes on, it looks like a circle with the letters “ABS” inside, and it does not necessarily mean that the whole brake system will not work. Your brakes will most likely still function, even if the ABS light comes on, but your ability to brake in emergency situations can be severely limited.

Engine Temperature/Coolant Temperature Warning Light:

Engine temperature and coolant temperature lights are often used interchangeably to indicate that your engine is overheating. The engine temperature is related to high coolant temperature and low coolant level since the coolant is designed to take the heat away from your engine. The light looks like a thermometer floating through the ocean.

Some vehicles have an engine temperature gauge as well as an engine temperature light that will illuminate while other vehicles only have a dashboard warning light. Normally this light is red, but some vehicles have an additional blue indicator light to show when the engine is not yet warm enough to drive more aggressively and will turn off after a few minutes of driving.

Low Fuel Warning Light:

Almost all cars have a fuel gauge that indicates how much or how little fuel the vehicle has left, but when the gauge gets close enough to empty, the low fuel light will come on. It looks like a fuel pump. Rather than indicating a potentially serious issue like the oil pressure or engine temperature light, the fuel warning light just means that you will soon run out of fuel, a different type of serious issue.

Traction/Stability Control Warning Light:

Even though many people consider them to be the same thing, stability control and traction control are different. They do work together – along with your brake system – to keep you more in control of your vehicle, but there are different dashboard warning lights for both systems.

When traction control kicks in, you will most likely see a car with squiggly skid marks behind it light up momentarily on your dashboard. If the light stays on, it usually means traction control is off or there is a problem with the system if you did not disable it. The same can be said of stability control, but the light usually shows the letters “ESC” for electronic stability control. Some vehicles allow both to be disabled at the press of a button and some do not.

Battery Warning Light:

The battery warning light means that there is a fault or failure in your vehicle’s charging system, not necessarily a problem with the battery itself. The light shows the outline of a battery with a plus and minus sign on either side. The issue could be the battery itself, but it could also include an alternator issue, an electrical issue, or a failure in the serpentine belt.

Transmission Warning Light:

People know that their engine can overheat, but many do not understand that the transmission and gearbox can do the same. The transmission warning light means that the transmission fluid has become hotter than it should be. This could also mean a bigger issue with the transmission. The light looks like a gear with an exclamation point in the middle.

Not all cars have a transmission warning light, but rather, the check engine light could illuminate if the computer module detects an inconsistency or fault within the transmission.

Power Steering Warning Light:

Many of the newest vehicles are equipped with electric power steering, and some have hydraulic power steering. If there is an issue, a steering wheel with an exclamation point will illuminate on your dashboard. Depending on the type of power steering you have, you can either top off the power steering fluid or you will have to take your vehicle to a mechanic to have it fixed.

Gas Cap Warning Light:

The gas cap warning light might not seem like an important dashboard warning light, but it could signal a more serious issue than just a loose gas cap. The light looks like a car with a fuel cap on the side and it functions as a wholistic system warning light rather than a singular gas cap issue.

When your vehicle’s ECU detects a leak in the fuel or emissions system, the gas cap light will come on. Checking the gas cap should be the first thing you address, but if the gas cap is tight, there could be something bigger happening within your engine that requires a professional mechanic’s help.

Diesel Vehicle Specific Warning Lights:

Diesel engines are different than gasoline engines, and even though most new cars do not have them, work trucks, some vans, and certain car models do feature diesel engines. Being different, there are three primary dashboard warning lights they have that regular gasoline vehicles do not.

The glow plug warning light will illuminate if the control system picks up a problem within the glow plug system. This is important because diesel engines use glow plugs to warm the combustion chamber before startup. Not only do they help start diesel engines during cold weather, but they also help maintain combustion temperature during and after engine running.

A diesel particulate filter and exhaust fluid are also used in diesel engines rather than regular gasoline engines. Both have their own system warning lights, both help regulate diesel emissions, and both are important regulatory components for diesel engines.

Other Important Indicator Lights:

Unlike the dashboard warning lights mentioned above, there are several other important indicator lights on a car dashboard that serve more as reminders than as signals of serious issues for your engine and its components.

Most people are familiar with lights like the cruise control indicator, fog light indicator, high-beam indicators, and turn signal indicators, but they are used more like indicators to show that these systems are currently running than problems within the systems themselves. There are four main universal indicator lights that display important information to you without indicating a serious vehicle problem.

Seat Belt Indicator Light:

The seat belt indicator light means that the vehicle detects that your seatbelt has not yet been fastened. Usually, it will blink and beep until you put your seat belt on, especially if you start driving before doing this. Most vehicles nowadays are equipped with an automatic weight sensor in the front seat that will turn the airbags on or off if it detects someone in the front seat.

Parking Brake Indicator:

The second important indicator light that is universal to vehicles is the parking brake or hand brake indicator light. If the parking brake is not fully disengaged, the parking brake light - light with an illuminated circle with the letter "P" inside - will stay illuminated until it is fully disengaged. Most vehicles will also beep if you start driving when the handbrake or parking brake is still engaged.

Windshield Washer Fluid Indicator:

Even though windshield washer fluid is not crucial to the operation of your vehicle, it can be very important when the weather gets bad in winter or to reduce glare if you have not washed your vehicle in a long time. An icon with a windshield and dashes will display if your fluid reservoir is low.

Door Ajar Indicator:

The last important universal warning light is your door ajar warning light. Most people are very familiar with this light since it is very easy to not shut one or more of your doors all the way. The light looks like a vehicle with one or more doors open, and many new cars will specify which door is not fully shut.