No, the lack of a brake controller wonít affect your lights so thatís not it. Iíd start by checking for a bad ground with the trailer wiring if none of the lights are working since the ground would be common to all lights. If it were only a specific set of lights not working I would start by checking that circuit.
Good luck, hope itís something simple!
2017 GMC Canyon - CCLB, 4x4, 2.8L Duramax, ARE Z-series shell
2013 Shamrock 21SS