If you have the 3rd light working, then you already have a brake signal going to the back of your van. This eliminates the fuse & switch. I would check the bulbs again. I've seen bad bulbs that looked good. make sure the bulbs are correct for the vehicle.. make sure they are installed correctly.
check the fuse then the bulbs then the brake switch
Please check the Brake light switch....The brake light switch should be located near or on the brake pedal (up on the stem of the brake pedal)
Check the fuse, check the bulbs and check the brake light switch, it should be one of those.
Check bulbs, fuses and brake switch in that order.
Check all the fuses. If not bulbs or switch that's all that it can be,
Bad bulbs or brake light switch.
Check the fuse, the bulbs, and the brake light switch.
If the brake light fuse is good and the brake light bulbs are good it's probably a faulty brake light switch.
AnswerThe bulbs for the brake lights are usually separate from the normal tail light bulbs. Check and replace the brake bulbs first, and if they are still not working examine the fuses, switch and wiring.
check your bulbs
If the bulbs and fuses are fine, it must be your brake light switch attached to the arm on your brake pedal.
Possible bad switch on the brake pedal? When you push on the brake pedal, it activates a switch, that switch turns on your brake lights. If the bulbs and fuses are ok, check the switch with an ohmeter.