Beyond “low gas” and “door open,” car lights are a unique language that many people cannot decipher. Although all lights have meanings that can be found in the manual that comes with the car, there are symbols that have universal meanings.

The most ominous light is the check engine light. Vague and unfamiliar, this light does not tell a lot about what has gone wrong.

Justin Leftridge, a retail service specialist at O’Reilly Auto Parts, said the check engine light represents multiple different aspects of the car because not everything that is being monitored can have its own light.

Coding tells the difference between issues when the check engine light turns on.

The codes can mean practically anything that is being monitored by a sensor, but almost all codes are available for translation online.

Codes are tested for possible fixes multiple times on multiple vehicles, making the potential causes of the light comprehensible and narrow. 

Alex Vibbard, store manager at AutoZone, said the most common causes of the check engine light are emission-related faults. 

An emission-related fault means there is an error with the emissions, which can be as simple as a loose fuel cap.

Vibbard said the tire pressure light comes on when the sensory reads that a tire is below a specific value, but the light also will come on to notify if tire pressure is too high. 

The tire pressure light’s solution is to figure out which tire is low or high in pressure and to notify the driver.

Another nearly universal car light is a red brake light. While the light can signal a parking brake being left on in some cars, it shares other meanings as well. Vibbard said the brake light relates to the brakes, but it can mean that the brakes are in need of maintenance, such as requiring brake fluid.

Although this is not universal, a service-required or maintenance-required light is standard in most vehicles. Vibbard said the service- or maintenance-required light functions notify drivers that their car needs work, but the issue is not as urgent as when a check engine light turns on.

The best way to know what the lights in your car mean is to familiarize yourself with the lights in the car’s manual. A lot of lights are universal, like the opened door light, driver seat unbuckled light and the dreaded check engine light.

But not all lights are universal, making it important to know what the car lights mean before they light up.