Whats wrong with my 1994 cadillac seville brake light?

Hi, I have a 1994 Cadillac Seville STS. The 3rd brake light is only half lit up, I just got it, and I dont know much on the car. Is it a bulb that I have to replace, or do I have to get the whole new light? Can anyone help me out?Whats wrong with my 1994 cadillac seville brake light?Its probably a bulb. The ony way to know for sure is to take it apart and look. The dealor should have a list of parts, and shoudl know if there is a bulb listed, or the whole unit.Whats wrong with my 1994 cadillac seville brake light?just a bulbWhats wrong with my 1994 cadillac seville brake light?there should be bulbs in that third brake light and apparently you have some bulbs burnt out, just change the bad bulbs.