Was there any resolve to this issue? I’m having the exact same issue on my wife’s 2018 JK. The new bumper has four fog lights and a light bar. I turn the fog light switch on and they flash on then stop and don’t work
It could be that you have to much on the switch if you have all those lights on the switch, it could be the Factory Relay if they are run off of one. Maybe add another relay for the light bar from the power wire to it if they are all on the same one.