Car warning lights don't come on just to annoy you. They only come on when your car needs maintenance or repair. The light might simply be alerting you to a minor problem to let you know you should take your car to a mechanic when you can for diagnostics. If one of the more serious warning lights comes on, though, you may need to pull over and shut your car's engine of as soon as possible. Here are the answers to questions you may have about your car's warning lights.
If the oil light in my car comes on does it mean the oil needs to be changed?
Newer cars can have something called an Oil Life Monitor System. Not all new cars have one, but some do come equipped with them. This is not to be confused with your oil warning light. An OLMS typically indicates that it's time to change the oil by literally displaying the words 'Change Oil' or something similar. When your car's OLMS indicates it's time for an oil change, it should be done soon, but you don't have to pull off the road and shut off the car. The oil warning light is one of those more serious warning lights that indicate your car needs immediate attention from a mechanic. It is usually instantly recognizable as it is a light in the shape of an oil can. If you have an oil pressure monitor, the oil light will usually be right next to it. If that light comes on, go to a mechanic right away if there is one within a few blocks. If there isn't one nearby, pull over, turn the car off and have it towed to a mechanic. Continuing to drive the car could cause serious damage to its engine that will cost far more to repair than the price of a tow.
Should I just add water to the radiator if the little thermometer lights up?
No, you shouldn't. When the thermometer on your instrument panel lights up orange or red, the engine is overheating, and you need to do something about it immediately. For some reason, the liquid coolant has stopped cooling the engine sufficiently. A serious leak could cause this, or the coolant pump might have stopped working. Continuing to drive the car in this condition could lead to serious engine damage and possibly even a fire under the hood. When this light comes on, turn off the air conditioner and turn the heater on high. This will help pull the heat out of the engine compartment. Take the car to a mechanic right away, if possible. If you aren't near a mechanic, pull over but do not shut the car's engine off. Leave the engine running for another 10 to 15 minutes with the heater on high, and the windows rolled down. You could consult your owner's manual for further instructions, but the safest course of action here would be to have the car towed to a mechanic.
What are you supposed to check when the Check Engine light comes on?
The Check Engine warning light is another possible emergency-type alert. It usually lights up yellow, red or orange in the shape of an engine, but some cars will simply light up the words 'Check Engine.' If it lights up red or is blinking, there is a very serious problem with your engine that needs immediate attention from a qualified mechanic. If you have an older car and the check engine light is blinking, it commonly means the engine is misfiring, and gasoline is actually being poured into the exhaust system. If this occurs, it will cause damage to the catalytic converter, which is very expensive to replace. If the Check Engine alert lights up red or blinks, pull over immediately, shut off the engine and call for a tow. A yellow or orange non-blinking check engine light is not as serious, but the car should still be taken to a qualified mechanic as soon as possible to have it checked out. If the light is ignored, the problem will only get worse. You could try making sure your gas cap is tightened completely. A loose gas cap can trigger a check engine light in some cars.
What is the warning light that looks like a pipe wrench and glasses?
That is the 'Service Vehicle Soon' warning light. When this light comes on it means there is something wrong and you need to take the car to a mechanic to have it repaired as soon as you can. Possible problems could be electrical or something wrong with the lights. Check to make sure the brake lights, headlamps, hazard lights and turn signals are working properly before you drive the car any further. Driving the car without brake lights or turn signals could cause a serious accident. Other possible causes include trouble with the traction control system or a communication breakdown between modules.