Yes poprichie I realize there is no voltage without the brakes engaged. My thought was, is there a loose ground connection tied into the magnets. My brake controller is a Prodigy P2. It is almost like an intermittent issue, sometimes it works fine.

This is something that I didn't know awhile back, that you can damage the Prodigy if you pull the cable out on the brake away switch with the controller plugged into the trailer. I then read the instructions and it does say that.
You may have a bad connection to the Prodigy. To test the trailer brake wiring and magnets, pull the emergency break away switch cable, with the trailer unplugged from the tow vehicle, try to pull the trailer, as this will apply a full 12 volts to the brake magnets. If all 4 wheels slide or nearly slide the trailer brakes are ok. replace the break away plug into the switch as soon as possible, it left on the magnets will over heat.

That sounds like another easy test to try also, thanks poprichie. Also I installed the prodigy and I have not ever pulled the break away switch on the trailer with the cable connected to TV since I have owned it, but its nice to know that little tid bit of information for the future.

In PA we have to have our trailers inspected annually, and the break away switch is one of the things they check and they do it just as I described.

I agree with inspecting the break away switch annually, I just had the hubs repacked at camping world and they checked all that out then about 2 months ago, I just dropped off the trailer for service, so it wasn't still connected to my TV while they did the work also.

I went out just now to verify the voltage at the terminal block on trailer frame at pin 6 which is the electric brake connection. Had my son press brake pedal and had between 0.9vdc to approx. 1.7vdc while he was pressing and releasing the brake pedal in truck. Then had him press the manual over ride lever on the prodigy and had approx 7.2vdc at same location on terminal block. I will do the break away test as soon as my wife can help me real soon.

My terminal block is different than yours it only has 4 connections on it. Yes, with the Prodigy lever pushed over the reading you get at the brake blue wire terminal should read within 1 volt of what you have the Prodigy set at. I said 12 volts but that is only with the Prodigy turned full up. The Prodigy will increase the voltage when you are braking up to your max setting. You may also have a boost set, I don't my trailer is lighter than yours and if I set to boost 1, I get very abrupt stops.

follow up
 

I did a test of pulling the break away switch with the trailer unplugged and then tried to pull it to see if the wheels were locked up. It looks like only my front left (driver's side) locked up and the other 3 would still turn. I could definitely feel them engaged as it took a lot of power to get it pulled slightly. Also I tried to check it a few times since it was my 8yr old son helping me watch the wheels and explaining what to look for.

However, a couple of times it felt as if when I pulled the pin out none of the brakes were engaged, and I was able to pull away very easily without the added drag noticed when the brakes were engaged before, and I would put the pin back in place and pull it out again and then it would engage the brakes. Not sure if this is a sign of the break away switch going bad?

One thing I did also was verify that my truck would show a connection on the brake controller fine while hooking up to another trailer. I went to drop off my trailer and was able to hookup to another guys trailer there to test it out. I plugged into his trailer and disconnected about 5 or 6 times and each time the brake controller in my truck showed up connection fine. I then tried to hook back up to my trailer and no connection. So I feel pretty confident that the issue lies further back on the trailer and leaning towards something in the brake wiring, magnets, or break away switch itself. Any other suggestions is much appreciated.

On a side note, it was a little irritating when I had stopped in camping world today to pick up a couple of filters for the AC unit, the guy helping me at service counter said he remembered me since I was a frequent customer, I had asked if they could hook up their tester to verify my TV connection is good and they told me it would be a minimum charge of at least $30. Ok I guess I will check it myself :confused:

I think you have listed about everything, I will say that the wire connections under the trailer to the magnets get corroded and don't work, I always solder mine. When you disconnect the magnet wires, use your ohm meter to check them, the ohm reading for Dexter magnets should be 10 and 12 inch brake magnets resistance should be 3.2-3.5 Ohms.
If out of range they need replaced.
https://www.etrailer.com/question-17395.html

Thanks again poprichie. That is some good information from the link on testing the magnets. When I was under the trailer yesterday I did notice that it was wire nuts used to connect the magnets to the rest of the system, so there might be an issue like your suggesting with the connections to the magnets. I had to take the trailer back to storage lot yesterday, and getting ready to start the work week, so might be a week or so before I am able to get back to testing the next steps. I will update once I either find the issue or not. Thanks again for the assistance it is much appreciated.

fixed
 

Well the problem is fixed finally and the brake controller is now showing good connection. The final fix was a combination of replacing the entire wiring system from the terminal block on the trailer frame all the way back to the brake magnet connections. Also one magnet was replaced as it was questionable. One thing that I have found out through this whole process is that the previous owner was not really up to par on preventative maintenance for the trailer. One example is I had asked him when was the last time he had the bearings repacked?, his reply was "I have never done the bearings" this is a 13 yr old trailer, what :eek:, so of course that was one of the first things I completed. So at least now I feel a little more comfortable towing this trailer around. Thanks poprichie and all the rest for your responses along the way.