One running light stays on

[Sunshyne]

I noticed that one running light is still on, although, all other light are off. History: Hubby took the running light off to put new vinyl stripes on. He bought a new light and recently installed it. Can you give me a reason why this light is staying on?

 

[Gronk]

Only the one light that he took off is on? Is it an LED light? If so, there is a possibility that the two wires are hooked up backwards. A lot of the vehicles now are switching the ground instead of the positive side so it may have power and getting its ground through other lights.