It means that the computer has detected a fault and has stored a problem code. You can use a code scanner to find out what's wrong. It's probably something like an oxygen sensor, EGR valve, MAP sensor or something else that affects the emissions, but you won't know for certain until you check for the code.
It is most likely your oxygen sensor
the emission lights could be comming on because your catalytic converter is not working right.
Mal function in the emission control system
most likely an oxygen sensor
Computer has detected a problem with the emission's system.
a malfunction has been detected with the emission control system
Usually a problem in the emission control system - have vehicle scanned to determine the problem
First, you need to fix whatever's wrong, then you unhook your battery cable for about 30 minutes, then re-hook. If it comes back on, you have a problem that was not addressed.
Have vehicle scanned and codes cleared - usually a problem in the emission control system
you bought one of those? what a weirdo
Have vehicle scanned to determine the problem
Usually a problem in the emission control system - have vehicle scanned to determine the problem