Traveling up highway 99 was not able to miss pot hole that jarred truck and trailer pretty good. Noticed that RPM's were higher than speed I was traveling. Friend following radioed that my tail lights had come on. Light switch was off. After stopping, we checked fuses, wiring, pulled trailer plug but lights stayed on the truck. Took the fuse cover on dash off again to check and friend said lights went off. Resumed on and convertor and lights were fine. Has anyone had this problem?