Car Warning Lights: Is My Car Going To Blow Up? Myths & Facts

by: Theodore Olson


Today’s vehicles are equipped with an array of warning lights. Of course we’re all familiar will the seat belt warning and the door ajar indicator; however, with the automotive industry’s technological advancements there are a number of warning lights that can be quite alarming.

Following is a Question and Answer Guide on some of the more common Warning Light concerns. Note: due to the frequency of the Check Engine Warning Light, it has a section all its own. Visit www.repairtrust.com/check.html.

1) SRS Light (Supplemental Restraint System): the supplemental restraint system is your Airbag System. It may incorporate a variety of active, passive, and even pre-safe technology depending on the vehicle. Given that the SRS System is a safety system, it is well monitored with numerous sensors and automatic self-tests. The slightest malfunction in this system illuminates the SRS light.

"Can the vehicle be driven with an SRS Light on?" Yes, at the owner’s risk. There are thousands of vehicles on the road without SRS technology.

"Is the airbag going to blow up?" It’s unlikely. When the SRS Light is on the system is inoperative.

2) ABS Lights: The Anti-Lock Brake System Warning Light is another common occurrence in today’s vehicles. The ABS system helps to keep you from skidding out of control during braking by limiting your wheels from locking up/skidding.

The ABS system is often integrated with traction control and stability systems, all of which are designed to keep you safe during panic stops, wheel slippage, and handling.

"Do I need brakes?" You might, but that’s not why the ABS Light is on. The ABS Warning System does not monitor disc brake pad or disc brake rotor wear (see the Padlight Warning section below)

"Can the vehicle be driven?" Like the SRS system, the vehicle can be driven at the owner’s risk as there are many vehicles still on the market without the enhanced safety features of ABS.

"Why is my ABS light on? How do I reset the ABS Light?" These are simple questions with a multitude of answers depending on the vehicle in question. For a QUICK and FREE solution, follow the information and guidelines for Resetting Check Engine Light, and apply them to your ABS light.

3) Low Coolant Light: The Low Coolant Light will come on when the coolant drops below the coolant level sensor—generally one to two quarts. If this light is on, there are two primary possibilities. The most common is a coolant leak. The other is an electrical fault in the warning lamp circuit. Have them checked out.

"Can it be driven?" If there are no major leaks, the vehicle is not overheating (and does not start to overheat), and there is still some evidence of coolant in the overflow bottle, it can be driven. If you can see coolant leaking on the ground—tow it. When in doubt, always tow it!

4) Red Oil Light On: Stop driving immediately and shut the engine off! If a Red Oil Warning Light comes on PAY ATTENTION.

The best case scenario is that your engine oil is a little low. The second best case scenario is that there is an electrical issue with the Oil Level Warning System circuit.

First, follow your owners’ manual’s instructions to check your oil. If low, add as recommended—make sure you don’t see it dripping or pouring out on the ground, which would indicate a “major” engine leak.

If the oil is not low and your engine is making ticking, knocking, or unusual noises, Tow it!

If everything appears ok, and you’re a bit of a gambler, it may just be an issue with the warning lamp circuit. In this case, get your vehicle checked out at your earliest convenience.

The worst case scenario is internal engine damage.

Note: many of today’s vehicles have very sensitive and sophisticated Oil Level Warning Systems. You may be alerted of oil level too high, or oil level too low. Again, refer to your owners’ manual’s instructions.

So whether it’s a 1993 Ford Aerostar Check Oil Light, or a question of “Why does oil light flash in Saab automobile,” PAY ATTENTION!

5) Red Brake Warning Lights: Generally, Red Warning Lights mean DANGER. In the case of a Red Brake Warning Light, there may be a hydraulic brake fluid leak. If the brake pedal feels abnormal or spongy—don’t drive—Tow It!

"Can I drive it?" If the car is stopping ok, and you’re a gambler, go ahead. If the brake pedal feels different than usual, or if the vehicle is not stopping properly, don’t drive it!

Note: make sure that your emergency brake is not on or partially engaged, as this will illuminate a Red Brake Warning Light.

6) Yellow Brake Warning Light (Padlight): This is an early warning system for brake pad wear. Essentially, as your disc brake pads wear down, at a certain point a sensor is tripped to alert you that you will need brakes soon.

"Can I drive the vehicle, and for how long?" Yes, you can continue to drive. How long depends on your driving style. City drivers (city driving is generally harder on brakes due to the constant stop and go) will likely need their brakes addressed before someone who does primarily highway driving.

"Will I do more damage to the brakes?" Depending on how long you continue to drive you could conceivably wear your disc brake pads down to the metal backing plate, which could then damage your disc brake rotors and, in rare cases, the disc brake calipers. However, with many of today’s brake systems, the replacement of the disc brake rotors along with the disc brake pads is required or strongly recommended.

Important: It is better to have your brakes checked early to increase the possibility of saving money by not having to replace the rotors. However, many of today’s brake disc pads and rotors require replacement not due to wear, but due to rust and corrosion; thus rotor replacement is often necessary anyway. Brake calipers rarely need replacing during regular brake work.

7) Air Suspension Lights (Airmatic, Air Ride, Hydraulic Suspensions): Suspension Warning Lights illuminate when the suspension’s monitoring system has detected a fault. Often there is a leak—either air or hydraulic fluid.

"Can I drive it?" Sometimes. But if the suspension is lower than usual, and/or the vehicle just doesn’t feel right—Tow It! Extensive damage could result if the suspension drops too low while driving.

Note: air suspension system repairs are best left to the best, state-of-the-art service center you can find, preferably a dealership.

8) Tire Pressure Warning Light: This recent technological development causes quite a bit of confusion. Put simply, if your tire is getting low on air, your car lets you know via sensors mounted in various places depending on the model.

"What is the low tire pressure warning light reset procedure?" Sometimes the reset procedure is as simple as pressing a button. Other times one has to set the tire pressures, recalibrate the on-board computer, genuflect and cross two fingers. Check your owners’ manual or call a specialist or dealer.

Note: Local shops and franchises (for the most part) lack familiarity with Tire Pressure Monitoring Systems given that this is a fairly recent technological development. You can refer to How to Reset Check Engine Light, and follow the tips, and suggestions for getting it reset.

9) Emission Warning Light: This light is similar to the Check Engine Light. Many European models such as Volvos have this type of Warning System. It’s essentially letting you know that an emissions component has failed or detected a fault. Follow the Check Engine Light information and tips to address this particular warning light.

Note: make sure you take it to a shop equipped to handle emissions work.

10) Resetting Oil Lights (Oil Change Warning Lamps): Whether it’s a Toyota Oil Light Procedure, an Oil Change Warning Light Reset 2005 GMC Envoy, or the process to Reset 1999 M3 Oil Service Light, all require a specific course of action.

Most owners’ manuals have this information. You should find it under maintenance or oil service. You can also call your local mechanic, who resets oil service lights everyday on a variety of models. A dealership will certainly have the information; however, finding someone in a dealership who can translate it effectively may be difficult.

If the above fails, see the process for Resetting Check Engine Light.

Note: several European models require special tools to reset the oil service light, thus it’s best to call or visit a specialist or dealer.

Note: This information is not a substitute for your vehicle’s owners’ manual. It is meant to be a general guide. Always refer to manufacturer vehicle-specific guidelines.

Note: PAY ATTENTION to how you are billed for any of the above warning concerns. Because of their technical nature they can get “unnecessarily” very pricy, quickly.


About The Author

Theodore P. Olson (Ted) holds extensive certifications from Mercedes-Benz, Toyota, GM, and ASE. He is the author of eight books and numerous articles on the automotive service industry.

http://www.repairtrust.com