Brake issues

[smity70]

Thanks in advance to input and advice. Bought a new 2012 27.5BHS Eagle superlight. The day I picked it up (May 1 2013) the service techs had wired the battery backwards and it kept blowing fuses, not to mention completely frying my existing brake controller. After replacing controller it was noticed that the brakes would not apply fully, 1 would lock up and the others not so much. With a little craphouse diagnostics I was able to tell that there was loss of voltage after the 5th's rv plug pigtail but could not isolate it, about 1.5v drop (12.7 to 11.2). It was also noted that there was about 3-6 ohms of resistance after this point also, it to cannot be isolated. I took it to the dealer and they did some things (I am pretty sure they let it set in the lot for 10 days and hoped the brakes would rest and be good) and said it was fixed- it wasn't. I have towed with different vehicle and braking was not any different, very weak, I have towed a similar trailer with both TV's and can lock brakes easily. My 5th slows somewhat if under 25mph. The tech on my advice says he bypassed the brake wiring with a new piece of wire to trouble shoot an ground fault and could not get the brakes to work with this attempt, size of wire and how it was done is not an answer I have. After this dealer took the the brakes apart and said the brakes were glazed. They would replace them all- it was said and done. Yeah, it didn't fix anything (I wasn't surprised). Now they are at a loss and I am too. They last told me "we don't know what to think" and left it as if I was supposed to figure it out. They are currently waiting for Jayco to call back and give them further inspiration. In the meantime I did what any normal dude would do and found the most appropriate forum to ask some questions. Let me preface- I am not an electrician and have a basic knowledge of how it works, trailer brakes confound me after reading a lot, and I hope to not sound like an idiot or expert.
1. Should I lose voltage after the male pigtail (the one that plugs into the truck and connect to the trailer wiring, and it is consistent down stream)?
2. Should there be this kind of resistance (the magnet thing really confuses me here)?
3. Any suggestions on what to check and where to look?

Thanks,

A New Jayco Guy-smity70

[RVhiker]

There's lots of diagnostic info on electric trailer brakes in this: Dexter Axle Manual.

1. Should I lose voltage after the male pigtail (the one that plugs into the truck and connect to the trailer wiring, and it is consistent down stream)?

Yes, some amount. The greater the distance from the source, the lower the voltage.

2. Should there be this kind of resistance (the magnet thing really confuses me here)?
3.2 ohms per magnet. See the Dexter manual.

3. Any suggestions on what to check and where to look?
I'd check the amperage draw at each magnet with a full 12 volts applied to the system. If you don't get about 3 amps at each magnet, you know you have a wiring problem somewhere. You could also check the amperage as it comes out of the brake controller and it should be in the near neighborhood of 12 amps (4 X 3). I found some really poor connections in how my trailer brakes were wired, especially in how trailer umbilical was attached; you could check those connections to see what you uncover. You could eliminate your brake controller as being any part of the problem by connecting a well charged 12 volt battery directly to your brake wiring and make voltage and amperage measurements. Amperage is easily measured with a 12 volt clamp on amp meter; it's a tool I often use when checking trailer wiring issues and is not too expensive. Don't leave your magnets energized longer than you need to test them, they can over heat.

Could possibly your brakes not be adjusted correctly? By the way, this should be an easy problem for your dealer to diagnose. if your dealer can't diagnose it, perhaps they also don't know how to adjust brakes.

Since your dealer can't diagnose the problem, perhaps Jayco would approve you taking your trailer to another repair facility - hopefully one that has knowledge of electric trailer brakes. It does not sound to me like your dealer is competent in the repair of brakes. Maybe you should give Jayco a call yourself. Or call Dexter. Come to think of it, when I had a brake issue Dexter was much more helpful with the warranty than Jayco.

[smity70]

I kinda agree dealer is not where they need to be tech-wise, I am an idiot and have a better handle on this so far. I will follow you instructions and post back when I determine cause. Thanks for the direction.

smity70