How do you turn off check engine light on Volkswagen?

Generally, the CEL (check engine light) is generated by an emissions related error.

Many auto parts places can "code" your car to tell you what you need to fix.

Fix the problem, the light should go out.

Other than that, you could have the code cleared via above or by disconnecting the battery, but it will probably return if you don't fix what was wrong in the first place