[1bigwhitetruck]

My 05 titan had the same problem with trailer lighting. Dealer said that I had a recall. They installed a bcm sub harness that has inline fuses to the turn signal wires. Told me everything now works fine. Well plugged into a trailer and the lights still did not work. Got a buddy that works for an infinity dealer to pull a wire diagram for me and we found out that the bcm was not sending a signal out to the turn signal for the trailer. The truck turn signals worked fine, but had no trailer. Took it to the dealer and got the run around about how my trailer is causing my problem and that I should get my trailer rewired to the vehicle. My trailer works on my 07 titan but not my 05. So I pulled my trailer down to the dealer (me knowing that it needs a bcm) and told them to figure it out. Rewire the trailer to the vehicle if it needes it and if it works I will pay whatever. The tech actually rewired the trailer and the lights still did not work (no surprise). I called the service manager and arranged a meeting to discuss my lighting isssue. Met with the manager and explaned to him what was going on and that I had an infinity mechanic inspect my bcm and found out it was bad. He called in the writer and the tech. The writer and the tech sat there and told me to my face that the bcm is functioning normal. That my problem was in the trailer. Had them plug the trailer into another titan in front of me and the manager and it worked fine. Plugged it into my truck and it don't work. Service manager go very upset that it had gotten to this and replaced the bcm for me for free. If you want I can get the wire diagram for your truck and you can test the two wires and see if you have output.