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Electric trailer brakes - controller or trailer problem???

Ronsii

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So we have several trailers and several trucks we tow with... the new dodges 2016,2017,2018 quit working with the newest trailer... a 2019 PJ 25'dump w'dual tandem 7k axles, trucks work fine with several other similar(big tex,mirage) trailers and the PJ trailer works with my 97' f250. All I can figure is it's something to do with the integrated trailer brake controller in the newer trucks.... because everything is wired right and nothing has changed in either vehicles or trailers since it quit working... and was working great for the first couple months we had it...

Also I have checked the wiring ten ways from sunday and everything checks out electrically???? any ideas or suggestions would be greatly appreciated :)

pj25dump-junctionbox.jpg
 

Ronsii

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I think we tried leaving the truck running??? hard to say we were plugging things in an out so much???

These are straight electric axles..drum brakes the kind with the electric magnet that rubs on the face of the drum to lever the brake shoes against the drum.

They're actually the same exact axle on the new(PJtrailer) as one of the older Big tex gooseneck(pic in another thread with a kbota skid on it) that works great with the new trucks...so far ;)

When I plugged it into my truck with a reese pilot aftermarket controller the brakes on the PJ work flawlessly... in fact for thre first few months they worked flawlessly on the 2018 5500 ram pickup???? nothing has changed... no new plugs/sockets/wires....
 
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Ronsii

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It's like the integrated controller does NOT see the brake(electrically) because it will not give you a warning when it gets unplugged either and it will not illuminate the trailer brake lights(rear) WHEN you use the manual application lever for the trailer brakes. Trailer brake lights(rear) do work when the vehicle pedal is depressed and all the other light in the trailer work great no dimming/flashing/shorting...

Also the ground through the plug is great and works the lights solid even when the trailer does not have a ground path through the hitch.

One main difference I can see with this newer trailer is the lighting is 100 percent LED... so a bunch of diodes in the circuit whereas most of the other trailers have a mix but I think we have switched most of them to LED on their tail lights...
 
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Ronsii

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And here is an annotated pic of the junction box up in the neck of the PJ trailer, same pic as earlier I just added the text.
pj25dump-junctionbox.jpg
Everything seems right... when you pull the breakaway switch the 12volt form the battery get connected to the blue wire(brake) and will light up a test light at the end of the trailer plug and also locks both axles up... bu then again so does my truck when it is connected to this trailer.
 

heymccall

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I'd like to know the resistance measured between the blue and white wires (elec brake feed & ground).
I'd expect 1.0 ohm.

I'd like to think that I'm a bit of an ITBC expert.
 

Ronsii

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I think it was a little lower than 1 ohm... but it's been a week or so since I checked that part. I will recheck along with the ohms on the other trailer axles that are the same. I always had my trailers wired with one of each electric brake assembly wired to a ground stud right next to the backing plate but this one and the big tex are running a wiring harness that brings both wires from the brake sets right up to the junction box.

One other thing... I am not sure about the 7k rating on the axles, one of the guys told me that.... but I think they are 10k axles - guess I gotta get under and see the tags.

In the past I have also experienced brake wires shorting out on other trailers we have had... and this is NOT like that, this appears to be something to do with the new integrated controllers not activating themselves because of some sort of programming... either to do with a voltage feedback on some other electronic variance(cap./ind./res.) on the brake wire coming from the trailer. I didn't really check for high resistance crosstalk on any of these wires because I originally thought it was a connection issue... but the more I research it I believe it to be an electronic issue to do with the ITBC. If need be I have over 60k worth of hi tech test equipment I can start putting after this thing :)
 

RZucker

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I think it was a little lower than 1 ohm... but it's been a week or so since I checked that part. I will recheck along with the ohms on the other trailer axles that are the same. I always had my trailers wired with one of each electric brake assembly wired to a ground stud right next to the backing plate but this one and the big tex are running a wiring harness that brings both wires from the brake sets right up to the junction box.

One other thing... I am not sure about the 7k rating on the axles, one of the guys told me that.... but I think they are 10k axles - guess I gotta get under and see the tags.

In the past I have also experienced brake wires shorting out on other trailers we have had... and this is NOT like that, this appears to be something to do with the new integrated controllers not activating themselves because of some sort of programming... either to do with a voltage feedback on some other electronic variance(cap./ind./res.) on the brake wire coming from the trailer. I didn't really check for high resistance crosstalk on any of these wires because I originally thought it was a connection issue... but the more I research it I believe it to be an electronic issue to do with the ITBC. If need be I have over 60k worth of hi tech test equipment I can start putting after this thing :)

Just for the hell of it, have you put a jumper cable between the truck and trailer to verify the ground? I know... simple stuff.
 

Ronsii

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Just for the hell of it, have you put a jumper cable between the truck and trailer to verify the ground? I know... simple stuff.

No, not yet but that is in my list of standard things to do ;) but like I said earlier all of the lights work flawlessly not even a teeny tiny blink when doing any of the testing... although since you mention it.... one thing we have done in the past with the 2016 and 2017 trucks is use a 'single' jumper cable to reach from the truck battery + to the trailer battery + when the battery is too low to dump.... this could technically overdraw the wiring ground in the trailer/vehicle connections when the hitch ground is not 100 percent conductive... but if that ground circuit failed I suspect the lights would have issues.... and it doesn't explain the 2018 3500 truck not working either
 

RZucker

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No, not yet but that is in my list of standard things to do ;) but like I said earlier all of the lights work flawlessly not even a teeny tiny blink when doing any of the testing... although since you mention it.... one thing we have done in the past with the 2016 and 2017 trucks is use a 'single' jumper cable to reach from the truck battery + to the trailer battery + when the battery is too low to dump.... this could technically overdraw the wiring ground in the trailer/vehicle connections when the hitch ground is not 100 percent conductive... but if that ground circuit failed I suspect the lights would have issues.... and it doesn't explain the 2018 3500 truck not working either

Just a thought. Led lights don't need much for a circuit, I've lit up every light on a 40/24 set with a 9V battery for the fun of it. Electric brakes may need more .
 

Ronsii

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Yeah I know, I was also thinking the LED lighting *may* have something to do with the flakyness of this... but not sure anymore ;) btw... you can draw over an amp out of a 9v batt ;) the more I think about it - it's a computer thing... something to do with the ITBC.. on older controllers you can put a DMM on the plug and see voltage when you apply the trailer brakes... not so with these new controllers! they have to activate themselves first, so something is stopping them from doing that just not sure exactly what yet??? without the tech data on how the ITBC works I can only guess and reverse engineer things to figure it out... kinda like flying a 737 max without training ;)
 

grandpa

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If I remember correctly my dealer also told me if I unhooked the trailer with the pickup shut off, I would have to go back into the pickup and reset something.. I've only had it for a week and just got the 2way, fuel tank and tool box mounted, so I haven't had to pull with it yet. I suppose a learning curve will be coming my way.
 

heymccall

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Truck doesn't need shutoff to connect/ disconnect.
Integrated brake controllers are prissy, so I use them to flag when a trailer has an issue.
Trailers are built to a lower standard, ie...the resistance between the blue and white wire needs checked.
All of mine (9 trailers w/ electric brake) ground solely through the 7 pin.
The lighting doesn't matter one darn bit, save that they share the ground.
Aftermarket controllers don't look for feedback from trailer, unlike the integrated controller, ie...they operate with one magnet (3 disconnected).

On my ITBC GM trucks, I use a headlamp (not marker lamp) bulb across the blue & white to verify controller operation, by simulating the load.

Again, the resistance is tell tale.
Each magnet is 4 ohm.
So, two are 2 ohm.
And four are 1 ohm.
The integrated controllers need between 2.5 and 0.9 on brake circuit to operate.

Quick and dirty is to pull breakaway and verify 4 wheel braking.
 

Ronsii

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Turns out the trailer had a very slight short in one of the brake wires to ground... probably in the 200k ohm range... that's why I couldn't find it with normal resistance checking... and I really wasn't looking for a short to ground because the brakes worked perfect on regular controllers.... in the past I have had brake wire to ground short and you'd know fast!!! Even the trailer dealers fancy trailer electrical checker device didn't pick up on it.

You know with all this fancy electronic crap they put on these trucks would it really kill them to at least throw a code that says brake short to ground!!!

And yes, the very first check I did on site when it quit was pull the breakaway... It worked flawless :)
 

Ronsii

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Just thought I'd throw up a pic of the trailer lift, as I had it up when working on other stuff to clean out.
scissor-double-dump.JPG
 

heymccall

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You know with all this fancy electronic crap they put on these trucks would it really kill them to at least throw a code that says brake short to ground!!!
Your aftermarket controller didn't care at all, either. I think a tekonsha P3 will indicate short to ground.
 

Ronsii

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Your aftermarket controller didn't care at all, either. I think a tekonsha P3 will indicate short to ground.
Didn't seem to care at all... tried it on several trucks with standard contollers , after all it wasn't much of a short... I doubt it was even more than 20 milliamps draw to ground but that's enough to put the integrated controller into 'i can't do my job mode' In reality a few extra miliamps is nothing for what the eletric brakes draw.
I have experienced electric brake failure while driving because of shorts many times before... And you have to have a pretty good actual short to overload the controllers and even then they will try to recover if the short isn't permanent but have noticed on these new integrated systems they put a funny little box fuse inline so when you have a short on the road and lose the brakes you're done! And on top of that the funny little box fuse is practically non-existent in most auto parts store you go to! And..... When you finally do find it you need to get financing to afford it :eek: gotta love new vehicles ;)
 
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