Bulbs? Open wire from switch to lights? Corroded light sockets? Bad ground?
If you have flickering lights and smell wires burning in your Dodge Caravan, you need to get that checked out by a professional. This actually happened to me once too and my van started on fire, it was horrible.
do not now what type vehicle your working on.but check the back up light switch
look on the side of the transmission.
Could be the switch on the transmisson...I forget the exact name of the switch
have you checked the reverse lights switch?
Check bulbs and switch
There should be a switch under the dash activated by the movement of the brake pedal arm.
check the reverse light switch ,usually found on side of transmission
Check the fuses first. If the fuses are ok check the reverse switch. The switch is under the dash on some models, and on the transmission on others. A bad or misaligned switch is the most likely cause for no back up lights.
check the wiring from front to back
It may be a back up switch located on top of transmission.
Do you get a NO BUS That lights up on your mileage light?