My friend has an enclosed trailer that has electric brake problems. When the trailer is sitting and the brakes are applied it will lock up the wheels no problem. As soon as you start moving and apply the brakes they will not hold even at the highest setting on the controller. He has replaced the controller, magnets, shoes, and the wiring to the brakes on the trailer to no avail. 3 other trucks were hooked to this trailer with different controllers and they all have the same problem with this trailer. I measued the resistance of the magnet coils on each wheel and they are all ok. I noticed that when I measure the resistance of the coil and turn the wheel the resistance will jump up to 10 ohms then drop down to a normal 1 to 2 ohms which seems odd since that should not affect the resistance. I also measured the current to the brakes form the controller and when sitting the current is about 5 amps depending the setting on the controller but once you start moving with the brakes applied the current jumps around erraticly and will not lock up the brakes even at the highest setting.
This has me stumped along with my friend. All new parts and it still doesnt work. The trailer is only two years old and the dealer is of no help.
Am I missing anything obvious??
Jason
Could you have a grounding problem?
Was my though too but I know nouthing about elect breaks ??? I use the PP break system most times :'(
I would look at the ground also , also if the trailer has been sitting for a wile you might have some surfice rust use a wire brush on a drill or grinder to remove ...
My first though was ground but my 2nd is are the swing arms swinging the right way? The first time I did a brake job on electric brakes I put the arms on wrong and it acted like what you have. ::)
Andy
Sounds like it is trying to ground or short through wheel bearings if not what the other fellows mentioned.
Electric brake assemblies are made for left and right side actuation so check to make sure that is correct.
The only other thing I can think of is a short or ground in one of the magnets or wires when the magnet moves.
I have run a three axle heavy duty trailer with electric brakes for many years and never could get all six brakes working at one time. Very frustrating!
Eight weeks ago, I was slowing to make a left turn and some idot drove into the back end of the trailer and almost killed himself plus destroyed the trailer along with the box on the pickup. He hit the trailer so hard that the heads of the two back bolts on the plate popped off, the plate bent up and broke the hitch off the trailer, and then what was left of the gooseneck tried to push my fuel tank into the cab. So much for that trailer and his face too. That's a wake up call to pay more attention to the driving and forget the other distractions. Oh, he wasn't wearing his seatbelt either but the air bag probably saved his life but not his eye.
Gary
I pull a trailer everyday. Went to fix bakes a few weeks ago, and low and behold axles were upside down. Had to roll then half turn to get brakes to work.
Is it a tandem axle trailer? I had a similar problem. While up on the jack the tires seemed to lock up when brakes applied but once rolling down the road there was virtually no braking.
Turned out that I had a single wire broken that went to one of the four brakes that caused the problem. Spliced it back togerther and left skid marks all over the place. ;D
Kirk
If the resistance is going up then you have a bad ground as already stated, or a loose connection in the hot wire. Normally there are splices in the wires about 18" or so from the magnets. You may want to wiggle them while checking the resistance. A good way to check the ground is a test light between the brake ground wire back by the brakes, and the tow vehicle ground. If it even blinks for a split second while the brakes are applied then it indicates a ground problem. The hot side of the brakes should give a steady test light when the brakes are applied. I actually prefer using a test light ( #1157 bulb with leads attached) over a voltmeter for this kind of check, because you can see a quick transient easier with the bulb. It also puts a more realistic load on the circuit. Sometimes you can check between trailer frame and tow vehicle ground in the same way. Just be aware that not all trailer brakes are grounded through the frame.
VA-Sawyer
A new brake and gnd wire were run through the frame to the brakes. All of the brakes are grounded to this ground wire and not to the frame. I haved checked the trailer plug and the wiring to the fuse box on the trailer. We also ran a new gnd wire to the frame but that should not affect the brakes since we are using a seperate gnd wire connected from the plug.
I have verified the current and voltage when sitting to be ok. I also checked every magnet and all ohm out ok.
These are dexter axels with new magnets, backplate, shoes, and control arms/springs. The only thing not new are the drums. Is it possible that the drums are magnetized and this is counter acting the pull from the electric magnet causing the weak brakes?
He had mentioned that he borrowed out the trailer to someone and when they brought it back the brakes did not work as well from then on. This is the reason for the new brake parts.
This one has me stumped??
Jason
Jason
Electric brakes need current to work, not just voltage, and thus need very good connections at every point. First make sure the ground wire makes a good connection back thru the trailer plug to the vehicle and not thru the frame. Double check the pins on the plug and even replace both the plug on the trailer and connector on the vehicle. The pins on the plugs many times get corroded or compressed and make poor connections.
It usually is a poor corroded connection somewhere in the lines that causes poor brake action. If none of the brakes work, the main feed to the brakes is suspect.
Gary
Another thing I have found is if the drum has been over heated going down a hill or by dragging it can glaze the drum some how so that the magnet wont pull with enough for braking force. It's like as soon as the mag hits the moving plate it heats up a film on the plate that it acts like grease, could also be something to your magnetized drums though from over heating. ??? This is why I only use electric brakes for stopping and never to hold back when going down a hill. :P :-/
Andy
AD,
I will check for glazing when we pull the drums off this weekend.
Gary,
I have verified the current with my Fluke DMM. Sitting idle and applying the brakes the current is stable depending on the controller setting. Once the trailer starts moving and brakes are applied then the current is all over the map.
We are also going to check each magnet again with an ohm meter and a curent source to verify operation at each wheel. I will also solder each connection instead of using butt splices.
I will let you all know what I find.
Jason
If the drums are gooved from wear where the magnets ride you will need to have them machined smooth so the magnets make full contact, Fix mine.
Finally found out what was wigging out the brake controller. I ohm checked each magnet and measured the current with a 12V source. All checked out OK.
Finally decided to hook up each brake one at a time. Found that only when the front drivers side brake was hooked up the controller would wig out. Took off the drum. Magnet looked OK. Found that where Dextor clips the wire to one of the control arm's they had it rubbing on a pivot point. Pulled off the clips to find that the wire was frayed and about half way worn through. Spliced and taped that up. Hooked the rest of the brakes back up and all works fine.
I hate electric brakes >:( >:(
Jason
If you have ever tried to back a heavy trailer up even a slight incline and had the brakes engage from the compression of the coupler you wouldn't be very impressed with them either....
Murf
Most surge type trailer brakes have a way to lock them out for backing but what I hate about them is they are driving YOU in snow and ice and that ain't no fun!! :o :o
Glad you got it working Jason. 8)
Andy
I had three trailers with electric brakes to maintain and I had to go through the brakes every time the trailers needed to leave town. One, a 14000 lb gooseneck shop trailer, was a headache. I towed that mother 200 miles back to the shop in winter with no brakes so I could thaw it out and find the problem. The brakes decided to start working 2 miles from the shop! That was NOT a fun trip.
Anyone try the new electric disc brakes? A friend of my fathers who tows from here to Florida a couple times a year just changed over and loves them! I think he said the disc is stainless to keep from seizing when parked a while?
Ken
Andy, I know there is a lock-out on the coupler, but when ya' gets to where yer goin an ya gots to back up IN to the place it's a real PITA..... specially ifna' ya gots to get out into the traffic yer blockin to lock up the coupler.
Round here that's nearly as dangerous as saying "yes" when the missus asks if her outfit makes her look fat........
I used to hate those hydraulic brakes because of that backing up thing. I recently saw the "fix" for that. They tap into the wire for the back-up lights. The actuator is locked out electrically. No fuss - no muss :)
I haven't had any real problems with using electric brakes. I have them on a 5 X 10 utility trailer I built, they are also on the sawmill and on the 18' trailer I use to haul the tractor. I service the brakes about once a year when I grease the bearings. One thing I do is use "corrosion X" to treat the metal parts so they don't rust. I also use a little "anti-seize" on the pivot points.
VA-Sawyer
Call me crazy, but after all that monkeying around, wouldn't it have been easier just to take it to a good electrical shop?. Perhaps I'm fortunate to have a great shop near by, they just rewired a triple axle, 15,000lb. deck over trailer for me with parts and labor for $300. I think it was a bargin. I couldv'e messed around for a week with that thing. So, I stole the trailer for $500, had it rewired for $300. I'll modify the hitch w/ some welding and clean her up a bit and bingo! I was going to build my own but I would've had more than $1000 in steel alone, $500 for a used triple axle set w/ title (now I have an extra set) and still had to spend weeks building the darn thing. My philosphy is to pay the experts. I used to do everything myself, for me it became a false economy. I now pick my battles. There just aren't enough hours in a day.
I guess it would depend on the things that you feel expert in. I wuuld have taken it to and electrician for the wiring and a welder for the welding and and carpenter for the decking and a tire store for the tires and a mechanic for greasing the bearings and sevicing the brakes and a hitch place for the safety chains and hitch.................. hmm maybe some of us should just buy a new one and hope that the manufacturer knows what he is doing. :)
I went to them experts with my own plans in my hand. They looked at'em and said $6000. I don't know if they thought they had to draw their own on a CAD system or what. But, I left and went to a small welding shop. Had my trailor and winch all done up and $2500 total. It's actually cheaper to register a home-made utility trailor versus one factory made. Figure that one out. ::) I went to a good garage and got the breaks working off a new controller I bought. I couldn't figure the ground issue, they did it for free. I had hooked up the controller to the wiring harness under the stearing column myself and ran the wires back to the rear before-hand. The breaks and the wires coming to the hitch were all in place beforehand also, so it wasn't 10 minutes to complete at the garage. Then they slapped on the inspection sticker for $10.00. :) The problem I have is corrosion of the wires in the quick connect. Pain in the keister. >:(
There is a kind of grease stuff that you can pack in connectors . Even just spraying regular with wd-40 or anything else like that slows corrosion.
And it gums up the connectors, with all the dust it collects, so they can't make contact. ;)
all my connections get greased at the same time as the hitchball and load arms.
and once a year ALL parts involved in braking get replaced. incliding drums and even wires to the junction box for the brakes. and my brakes are run by their own circuit and box with 8ga wire. git-er-dun 8)
I don't use mine often enough to go through all that. I just jig around on the property. And real short hauls once in a grey moon.
As to keeping the connections from corroding, the pro's use a shrink tube that self lubes and seals as you heat it. It's awsome. But not all of the shrinktube is created equal, so get small samples from various suppliers and test them. then go hog wild to have what you need on hand when you need it. The stuff is top notch and the connection never corrodes. You also then only need the uninsulated type of crimp connecter. For exceptionally rough environs, say behind the rears of my one ton, you can double up and overlap the shrink tube. With the good stuff you can see the sealer oozing out as it shrinks.
There's shrink tube on all my wiring. I'm just plagued with the copper in the quick connect coroding from the road salt. It gets in the connector when the trailor's not hooked up to the truck. I pack some kiwi goo where the wires go into the back of the quick connect, but the flip up cover doesn't have a good seal I guess. Now, its broke off. So, I need to get a new one. I'm going to try an aluminum one next time. Right now its not priority since I don't use it in late fall or winter. I mostly haul tree seedlings and firewood in late years.
I was taught a nifty trick for keeping the trailer plug free of corosion in the winter.
Spray the insides of the plug really good with WD-40 or something like that, then give it a little spurt of spray-foam insulation. When it stops expanding, but before it sets up, slice off the excess and stick a piece of twine or wire into the foam.
When it cures you have a plug the exact size and shape of the cavity. Then you can fill each little pocket of the foam with dielectric grease and leave it in there when you don't ahve a trailer on the truck.
I will be sure to remember that Murf, Thanks. I may put a SwampDonkey twist to the concept, but looks like a good idea. ;)
The rules clearly state, any improvements, variations or twists to a wacky idea that actually works MUST be shared.
Void where prohibited by common sense, law, or wives. Some beer during assembly required. No purchase required unless you don't already have the junk around to do it.
8) 8) 8) 8) 8)
So, I bet you think your on a roll eh? ;)
:D :D :D :D