While lit up icons on your vehicle’s dash can be a nuisance, it’s important to know what they mean and the impact that a failed system can have on your vehicle. I’m going to try and enLIGHTen you.
I know, that was terrible.
So here we go. Here are some of the more common malfunction lights and what they mean:
This is the first one on my list for one reason: My wife had no idea what it was, and I was left wondering how many other people don’t know what it is. It’s a low tire pressure light. If you see it, at least one of your tires has dropped 4 psi below the rest of them. Most cars made after the early 2000’s have a tire pressure monitoring system. The early systems weren’t very accurate, as they used the wheel speed sensors to monitor pressure. The systems have since become much more accurate, using radio frequencies in sensors at each wheel to send pressure information inside the vehicle for you to see. Your owner’s manual will show you how to get to the readout screen on your dash’s information panel.
This is your engine coolant temperature light. If it comes on while you’re driving, your engine is overheating. You should safely pull over and shut your engine off to prevent any further damage. A few causes of this can be a stuck thermostat, being low on coolant/antifreeze, a seized water pump, or your serpentine belt has fallen off/broken. Don’t confuse this light for these:
These are examples of a low coolant light. There is usually a level sensor or float inside your coolant tank, and when the level gets low enough to drop the float down, this light comes on. Causes of this can range from a radiator cap that isn’t sealing, to a leak in the cooling system such as a water pump, hose, radiator, or heater core. A pressure test is suggested when you see this light.
This is your engine oil pressure light. People often believe this light to mean that they’re low on oil. While this may be the case, it is relative to engine oil pressure, not level. Again, if this comes on while you’re driving, safely pull over and shut your engine off to prevent any further damage. Your engine’s oil pressure is either too high, or too low. This can do catastrophic damage to your engine. Have the vehicle towed to your trusted repair shop.
This light means that your charging system is not charging. Most people believe that this means they need a battery and while that may be true, the battery may be collateral damage. Some causes for this light can be a faulty alternator, a blown fuse, bad wiring, or your serpentine belt has broken/fallen off. Driving the vehicle is not recommended, as it will only run until you run out of battery power.
Your seat belt. Put it on. Click it or ticket!
Fuel. If you see this light you should be seeking a gas station. A good practice to get into, is not letting your vehicle’s fuel gauge drop below 1/4 tank. I suggest this for a few reasons. It seems to “hurt” the pocketbook less when you fill up, if you get a flat tire in the middle of winter you can leave the car running and stay warm, and on some vehicles running on less than 1/4 tank can shorten the life of its fuel pump. This is especially true in GM vehicles. I can get into that another time.
This is a low brake pad indicator, commonly found in a lot of higher end imported cars like BMW, Mercedes-Benz, and Jaguar. Cars equipped with this system have an electronic sensor that is on the brake pads of each wheel. When the brake material gets low enough, the sensor makes contact with the brake rotor and trips this light. If you see it, get your brakes inspected soon. Don’t confuse that dash light with this one:
This light is usually on for one of three reasons:
- Your emergency/parking brake is on. Good deal.
- You are low on brake fluid and/or have a brake fluid leak. You may notice a very soft pedal that could go all the way to the floor. Bad deal. DO NOT DRIVE THE CAR if that’s the case. Tow it to your trusted repair shop.
- It’s accompanied by this light:
Your ABS light. This means there’s a problem with the Anti-lock Brake System. This should not affect your mechanical (normal) braking system. It just means that if you slam on the brakes or begin skidding on ice/snow, the tires will lock up instead of the car “pumping the brakes” for you (preventing the wheels from locking up, giving you some control while your brake pedal is to the floor). A faulty wheel speed sensor, bad wiring, or a programming error are some things that can cause this.
These lights mean that your traction control system is offline. This system works in a similar fashion to your ABS system. It’s designed to reduce the slipping of your tires when accelerating on slippery surfaces and maximize acceleration. A faulty wheel speed sensor, bad wiring, or a programming issue are some things that can cause this.
This is the most common light to see. Commonly referred to as a check engine light. This indicates a problem with an engine management system. There are so many things that can cause this to come on, that it’s best if you have a qualified repair facility do a diagnostic scan or procedure to find the problem. Even something as simple as a loose fuel cap can cause this light. If you see the light flashing, it means a catalytic converter damaging code/symptom is present. Driving the vehicle with a flashing check engine light is not suggested.
This indicates a problem with your Supplemental Restraint System or air bag system (they’re the same thing, one has a fancier name). If you see this light, this system is offline and your air bags may not deploy in the case of a collision. Typically an impact sensor or a wiring fault is the culprit.
These are maintenance reminders that are set by the vehicle’s onboard computer to come on at certain mileage intervals. Each manufacturer has suggestions as to when maintenance and inspections should be done. See your owner’s manual about when these are due. If you see this light, it’s time for service. These require manual reset procedures to shut the light off after the service is performed.
This light means that you are low on washer fluid. Most cars when empty will take a full gallon of washer fluid. A smart idea during the winter time is to add some isopropyl alcohol to your existing fluid or fill it with de-icing washer fluid to keep your lines from freezing.
If you own a diesel, specifically an older one, you’re probably used to seeing this light. When you turn your key on (not to start, just on) this light comes on and will stay on until the glow plugs have heated up enough to start the vehicle. Do not attempt to start your diesel until this light shuts off. If it is flashing at you, it means there’s a problem with the glow plug circuit and you should bring the vehicle to a certified diesel mechanic to have the problem diagnosed and repaired.
If you’re seeing any of these lights on and are looking for a qualified repair facility that you can trust to service your vehicle, look no further than the knowledgeable ASE Certified staff at Auto Works Diagnostic & Repair. We can fix that!