You will need to open the trunk and pull back the carpet. You will find three black plastic wing nuts that will need to be removed. You can then slide the light out (entire assembly)from the outside of the car. You will see a varity of wires leading to various bulbs. Remove the one that needs to be replaced (should twist out)and install the proper bulb (note that a new halogen bulbs should not be touched with your hands, read label on packaging carefully). Reassemble in reverse order.