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What?s That Yellow Squiggly Line Anyway? (What Warning Lights Mean)

October 23, 2025

You may have noticed when you start your vehicle, you’ll see several symbols light up on the dash.  They’re different colors and shapes, and sometimes it’s hard to figure out what each of those symbols mean.

They are warning lights and symbolize something in your vehicle is sending you a message.  It’s the result of today’s vehicles having lots of computers.  The good thing about having so many of these warning lights is they can let you know there’s an issue in need of attention before a more serious failure.  

Sometimes it can be challenging to figure out what each light means, so here are some of the most common ones.  One looks like your vehicle’s engine from the side, the Check Engine light.  It alerts you to something as simple as a loose gas cap to a far more serious problem like an overheating engine.  When the Check Engine light comes on, bring it into our shop.  If it’s blinking or flashing, it likely has more urgent issues, so bring it in sooner.

Another warning light looks like a genie lamp with a drip at the end, and it’s the engine oil light. When it comes on, it means something’s wrong with the oil pressure, and that can be a sign of serious engine problems.  Don’t ignore the oil light and bring it in for service as soon as you can.

One warning light looks like an old-style thermometer with a bulb at the bottom and degree marks on the side sitting in fluid.  That’s all about your coolant level, and when it comes on, your engine may be overheating.  It’s another one that’s telling you to bring it in to us for service quickly.

When your brakes aren’t working right, a light comes on that looks like a circle with a pair of half circles at the sides and an exclamation mark in the middle. Driving with malfunctioning brakes is dangerous, and it’s another warning light that should prompt you to get your vehicle looked at very soon.

If you see a light on your dash you don’t understand, try looking it up in your owner’s manual or bring it into us so we can help decipher it.  Warning lights are there to help you, and so are we.

Tuffy Tire & Auto Service Center Lockport
600 E 9th Street
Lockport, Illinois 60441
815-838-3700

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