Chuck&Gail wrote: One comment. DO NOT pull breakaway switch with TV brake controller connected. Some of them toast when that is done, unsure of Prodigy.
Good advice. Prodigy will fry as well -- it says so in the documentation that comes with the product.
I finally had a chance to do some testing today. I connected the truck to the trailer and then connected each brake to the bus bar individually. With the truck stationary I moved the manual lever to full power for each brake. I didn't have any help so I couldn't hear each brake close up, but from the truck I could hear a buzz each time I actuated the lever. For each wire the Prodigy would show C and at full power showed 6.5 on the display. I tried each brake several times. After the 2nd or 3rd try on each one the display would flash NC for several seconds and then return to displaying C. At no point did I get an OL. Even with all 4 brakes connected simultaneously I could get a reading of 6.5 and then it would flash NC.
This is very odd indeed. I can't think that there is a short in all 4 brakes? I am just at a complete loss
Have you disassembled and inspected the wiring inside the TV connector. I have been yanking trailers for forty years and many of the brake issues, especially the intermittent ones, have been a result of corrosion in the TV 7 wire connector. Just a thought.
It is possible that the controller is going bad. A poor connection inside could expand and go open creating the problem. Using several times builds up heat, then would cool down and make contact.
It still could be the same problem in the factory GM connector with the plastic keepers holding it onto the standard seven pin.
I would suggest connecting a load (lamp) to the TV connector to the brake pin and ground. Use the system to see if it fails connected directly to the TV.
Check the bacj side of the GM connector before spending much time chasing or throwing parts at problem.
Okay,
So last night I finally had a chance to dive into the brake drums and find the root cause of this problem. I went through all 4 and found no bad insulation or bare wires. So, I simply re-greased the bearings, cleaned all surfaces with "Brake Cleen" lubricated the shoe slides and pivot points, and slapped it back together. One thing I found odd was it took about 1 1/2 turns of the adjusters to get the shoes to contact the drums. Once they contacted the drum I back them off a couple of clicks and rotated the drum to ensure the weren't touching.
Lo and behold, I went for a test drive and never once got an OL from the display. In a local parking lot I did the 25MPH Prodigy setup routine, but I never did get the wheels to lock up. On a setting of 11 on the Prodigy I was able to get good braking coming from the trailer and at no point did they feel "grabby" or sticking.
So, the best thing I can guess is brakes were so far out of adjustment that it was causing the Prodigy to see an overload condition I'm not sure how well that explains the problem. I'm not going to say I'm 100% out of the woods until I get some more miles on this, but for now it seems as though the problem is solved.
KJ, I doubt you solved your problem, brake adjustment has no bearing on magnet current draw. If there is no short anywhere you will not get the OL on the prodigy display.
Assuming you followed the Dexter brake instructions exactly, there must be an intermittent short somewhere. Have you replaced the brake wire running through each axle? If you run replacement wire outside the axle, fastened with wire ties, you eliminate the chance of compromised insulation from the inside edges of the holes in the axle for wire pass-through.
Ray,IN wrote: KJ, I doubt you solved your problem, brake adjustment has no bearing on magnet current draw.
I didn't think it made a lot of sense either. Something has changed after finding no chaffed wires, adjusting the brakes, and then seeing them work properly. I can't explain it, and that's why I'm hesitant to declare the problem is completely solved. It works for now, but I'm not sure why. One thing I did do was lightly scuff the magnet surface with 220 grit sand paper and also the contact surface on the drum and then wiped them down with Brake Cleen. Maybe I was getting bad contact I'm really at a loss here and I wish I knew exactly the cause, and solution of the problem. I like to know WHY something works and when this "fix" seems to have been too easy.
Ray,IN wrote: Have you replaced the brake wire running through each axle?
Oh yeah, I did more than that. I installed two buss bars (like the one below) in the front compartment where the umbilical comes from the truck. I ran the brake + to one and the vehicle negative to the other. Then, using some 10ga wire I had lying around, I ran a dedicated + and - to each wheel, all in parallel. I realize that 10ga is overkill, but I already had it and I knew that would give me plenty of current protection.
That was one of the first things that I thought might be the problem due to the hodge podge of daisy-chained wires running to all the brakes. I was extremely disappointed when the problem still existed after all that work.
Like I said, I'm not going to declare I'm out of the woods yet. At first I thought maybe I had a bad Prodigy, but the confounding thing is it works fine on my buddy's utility trailer. Although, his trailer only has brakes on the front axle. Is it possible that 2 brakes aren't drawing enough current to "strain" the Prodigy, but when the 4 brakes of my TT are connected they cause the problem to surface? I've called Tekonsha in the past and of course they pointed to the vehicle or trailer wiring. I did discover that my controller is a version 2.4 of the Prodigy, not the updated 2.6. Does anyone know what the common problems were with the 2.4?
A Prodigy controller will not always fry if the emergency brake wire is pulled while the trailer is connected. I know it says it may fry, but mine didn't. Trailer stopped us fast, and made think I broke something. I had routed the emergency cable in a bad way, and it just got pulled out while turning. Lucky I was still in a parking lot, and at low speed.
I finally had a chance to make a long haul with the trailer last week. 500 miles round trip and I never once saw an error on the Prodigy or lost braking power.
I'm still not certain what I did to solve the problem, but it appears that everything is working fine for now. One thing I did do a few weeks ago was change the female receptacle on the umbilical. This was after my initial "fix" of cleaning and adjusting the brakes. So I'm not even sure of the new plug really had any effect.
At this point, I'm not going to mess with success. The brakes are working and I can drive without worrying.
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I'm not sure how well that explains the problem. I'm not going to say I'm 100% out of the woods until I get some more miles on this, but for now it seems as though the problem is solved.
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