Hello. I just replaced all my light bulbs in my rear lights (new turn signal/brake are the same bulb, new backup lights, and new tail lights).

When I turn on my headlights in the cab, my right rear brake light comes on. Only the right one. When I press the brakes, it gets brighter, when I release it goes back to a dim light. I also have brand new taillight circuit boards (see image), so I don't think the connection is getting crossed in there...


I have checked using a light bulb electricity tester (see image), and when I turn my headlights on, there does not appear to be any current running to said right rear brake light.