I am at my wits end with this tail light. The drivers side tail light/blinker doesn't work completely. The blinker is fully inop, the flasher is inop on the drivers side, the running light is inop. The brake light is inop if the head lights are on. I have replaced the bulb, I have replaced the reverse light, I have replace the brake relay switch. When I replaced the relay everything worked for half a day. I replaced it again and now back to nothing. I ruffed up all contact point for a good connection and didn't help. I traced the ground wire and didn't find anything. Any ideas?