What are they?
They are the little yellow lights that will sometimes pop up on your dash board. The process of this little light coming on is a very tough decision for your auto’s computer system. They could say check engine, they could have a little picture of an engine on them, Or they could say service engine soon.
What do they mean ?
They are there to tell you that your computer operating system found something out of range.[ That is out of it’s normal operating parameters.] In plain English it saw something that it did not like and thought it should make you the driver aware of the situation. Your owners manual may say that it is an emissions related problem and it very well may be, but it is not limited to that system.
They are Important.
They should not ever be ignored for long periods of time.
Although it is okay to drive and get to where you are going. Then as soon as you can set up and appointment and get it in the shop to have it diagnosed. The computer should have a code in it’s memory, that your mechanic can retrieve. It will almost always lead the mechanic in the direction of your problem or at least determine what system it pertains to. After this has been determined the problem will either be diagnosed or you the customer will be notified of the next step and cost of the diagnostic process.
The light will remain on if not repaired. This means that if the computer sets another code it will not be able to notify you of the problem because the light is already on. This is why it is always important to keep your car in tip top running condition and fix it right.