Hello all. Recently I installed a 12-LED third brake light bar on my enclosed trailer with a 4-pin plug that I tow with my 2018 F150 Platinum. I installed it primarily for a third brake light, but it can also function as a sequential turn signal, which I thought would be a nice bonus. When the truck is on but not running, the sequential function works as it's supposed to. However, if the truck is running, it will flash the entire bar with the signal and not flash sequentially. It seems strange to me. Both the truck and trailer lights are all LED, and everything works normally. Any thoughts as to why it would work sequentially when the engine is off but not when it is running, or suggestions on how to fix it?