Hi,
Just verifying that it is the tail lights that stay on and that it is not the brake lights that stay on? Do the lights glow more brightly when you depress the brake pedal? If not it is the brake lights.
If it is the brake lights, check that the brake light switch is OK .
Here's a [http://ww2.justanswer.com/uploads/baddad1/2011-08-26_192348_pages_from_br.pdf|link] that may help