Hi everyone, I wanted to share my recent experience with an issue I had with my trailer and its disc brakes as it might help someone who might have the same issue at some point. I went fishing yesterday and had no problems going in reverse with my trailer going down the ramp to launch or down the ramp with the trailer to load the boat. This was because there was no tension placed on the brake system going down hill. When I got home though, when I tried to back into the garage the brakes locked up and I could not go in reverse. My trailer is only two years old and I was surprised this happened with a new trailer. I have a Coastline trailer and it has a Titan hitch on it that you cannot manually override the actuator like you can on many boat trailer hitches. So I was stuck only able to go forward. I ended up having to drive over my yard because that was the only way to get out of my driveway based on the angle that the trailer was sitting. I finally got it to the mechanic that I use for all my boat work and after a a multitude of checks/rule outs for why it was locking up we determined that the trailer was working fine and there was not an issue with the actuator. We used the same electrical plug I use and he was able to back up the trailer with his tractor but as soon as we hooked it back up to my truck it would lock up and not go in reverse. So he determined it had nothing to do with the trailer but was a problem with the truck and most likely electrical. So we next checked the fuse for the trailer towing and back lights on the truck and the fuse was fine. Now it was really getting confusing. So I then pulled the boat and trailer to my truck mechanic to see if he could figure out what was going wrong with the truck's electrical. He spent an hour checking all the power going to the electrical harness and plug and testing the power when putting the truck in reverse. The blue wire for the backup lights(which is the wire which feeds the actuator) would intermittently have power and then not have power going to it. So this was very confusing. At first we thought it might be the wiring harness and that the blue wire might have a partial break in it inside the five pin plug. So we hooked the trailer up to his truck and the trailer would back up fine and worked perfectly. So there was no doubt that the trailer wiring and the plug were all working fine. It had to be something wrong with the truck's towing and backup light system. He checked the fuse again for the towing and backup lights for the truck and it was fine. I have a 2007 F150 and so he was really scratching his head what could be causing this. He then decided to check to see if there was also a relay in the fuse box for the towing and backup lights of the truck and it turned out that there was. There was both a fuse and a relay fuse. He changed out the relay and then everything worked fine. So it turned out that the relay was bad and therefore was only intermittently allowing power to be sent to the towing/backup light system so that the actuator on the trailer would work properly. All of this entire process took about 4 hours to figure out (marine mechanic and truck mechanic time). So here is what I learned from this experience (and I have had disc be sent to the brakes on my boat trailers for over 30 years including this new Coastline trailer):
1. Don't automatically assume because your trailer brakes lock up and you can't go in reverse that it is a trailer issue. It might just be a truck issue with either a bad fuse or relay fuse for the backup lights and towing system. Always check both of these. Also, the backup light electrical system on your truck is what works your actuator on the trailer. I didn't know that.
2. Don't have a trailer with disc brakes that you cannot manually override the actuator on the trailer. Most UFP trailer hitches have an easy way to do this and in fact my previous trailer had a UFP hitch and you could override it easily. My current Titan hitch on my Coastline trailer does not have a manual override which presented a big issue for me when I was stuck in the driveway not being able to back up because of the angle that the trailer was sitting. I think this is a bad design not to be able to manually override the actuator.
Sorry for the long post but I do hope this post helps anyone who might have the same issue down the road. It made for a very frustrating day for me and took a lot of time to figure out. I will now be carrying an extra relay fuse for the towing and backup lights for my truck. I already carry extra regular fuses.