On my 99 you open the taigate and remove the two retaining screws at the top of the tail light assemby. Then pull the assmebly free. There are 2-4 friction fasteners that will pull free. Then turn each of the bulb sockets to remove them from the back. They are held in place by plastic ears that fit into the housing. Pretty easy really. On the 99 the two screws are at the top and are easily visible, and are Phillips head screws. Other years may be along the top or inner side. I looked in my new/used 2004 manual and it shows how to do it. The screws on a 2004 are along the inside edge accessible when you open the tailgate.
with a screwdriver
Pull the carpet away from the back of the tailight assembly within your trunk. There you will find a series of plastic nuts that hold it in place; simply remove them and the light assembly will drop out. I hope this helps you. Mark
Open the rear hatch to access the mounting scews for the tailight assembly. Remove the scews and drop out the tailight assembly. The rest is self explanitory unless you have a fried circuit board for the taillights.
Probably going to need a new tailight assembly
BASICALLY YOU NEED TO REMOVE THE BUMPER ENOUGH TO LOOSEN THE SCREWS FROM THE BACK OF THE TAILIGHT ASSEMBLY TO SLIDE IT OUT THE BACK.
you have to take out the rear tailight assembly from inside the trunk, there are 3 bolts, the then Slides towards the rear of the car, the whole tailight assembly does, you also have to take off the cover inside the trunk area. it's not hard.
To replace the tailight assembly for a 2002 Ford F-150 you lower the tailgate and locate two hex screws that are inset two access holes by the light assemblys. Remove those two screws being careful not to drop them in the bed frame. The tailight assembly then cane be removed to access the bulbs. The owners manual does have very good instructions on this proceedure. Good luck.
Get into the trunk. Pull the carpet down behind the tailight assembly. Pull the bulb sockets back and out. Take the 10mm nuts off the back of the TL assembly. Side that assembly off the back off the car.
Locate the 3 tailight screws securing each tailight on the inside of the trunk. Remove screws and replace bulbs. The entire procedure will take you about 5-10 minutes and that includes removal and replacement time. Jim janesville, Wisconsin
Lift the hatchback and remove the 2 screws holding in the taillight assembly. You can then access the light bulbs from the rear.
Lower the tailgate, and you will see the bolts on the bed side of the taillight,remove the bolts. there are two of them and pull out tailight assembly.
From inside the trunk. The bulbs will plug into the back of the tailight assembly. You may have to move the trunk carpet away to reach it,