The light isn't the problem. The problem needs to be discovered and repaired. An OBD2 code reader can get the trouble code that tells what is wrong. If you just want to turn off the light and leave the problem, the code reader can do that. The light will come back on with the trouble. It's a "check engine" light, not a "check light", light.

The dealer of the car is the place to go IF you want to know the EXACT reason the check engine light is on so the emissions part can be cleaned or replaced.

Cuntry Boy the non-mechanic has no idea what he's talking about. Any shop can scan the computer in your car and reset it or tell you why it came on. If it was simply a loose gas cap, most small shops will do it for free. If the dealership wanted $400 then you probably have a bigger problem.

Take the car to a service station or dealership have them read the OBDII codes and have them fix the problem that was detected. You might try checking to make sure your fuel cap is on correctly and tight - that can turn on the check engine light sometimes.

You take it to someone who can plug in the computer to find out what's wrong with your car. You then fix the problem which some turn the light off

Its the gas cap. They want to charge me $400 to get it turned off. is there a bypass i can do? i know to reset the oil its turn key to auxillary and press the gas pedal 3 times and hold it. what is the way to do it?

Take out the bulb,cut the wire leading to it or get a new sensor and install it yourself

Go to a dealer, and pay the ~ $85 diagnostic fee.

Just find a good piece of dark coloured tape and cover it. Good as new!!