Help wiring question

[Jimthefisherman]

I have no running light on my trailer. To check my ground on the truck side, I tested the turn signals by using ground on plug and putting tester in plug on truck side. I get a pulsating signal I am assuming that this tell me that I hAVE a good gound. When I test from ground to brown wire, nothing. I traced the wire as far back as I could but see no problems with the wire. I pulled the licend plate light ad tried to connect it to the brown wire.. No luck, can I pull the taillight cover and pick up a signal??

[CatFan]

Have you checked the fuse in your truck?

[Jimthefisherman]

I looked at both fuse panels and could not identify fuse for r uning lights or trailer lights. Which fuse would you think would control the trailer running light. I assmed that because all truck running light appear to b e working that would not b e an issue. I understand that if truck was equipte with trailer package it would have fuses for trailer light, not on this ruck

[CatFan]

I looked at both fuse panels and could not identify fuse for r uning lights or trailer lights. Which fuse would you think would control the trailer running light. I assmed that because all truck running light appear to b e working that would not b e an issue. I understand that if truck was equipte with trailer package it would have fuses for trailer light, not on this ruck

If your trailer plug isn't factory wiring it still could be plugged into the factory harness. What truck do you have?

[Jimthefisherman]

Have a 92 silvarado, I tried to pick up a wire from the license plate lights with no luck. Went back to the back of the light plug and discovered that I had connected to the black wire rather than the brown. I now have trailer running lights.
Thanks for your willingness to help.