Electric Brake problem, can you help??

DandS · Senior Member

Electric Brake problem, can you help??

justcruisin01 · Guru

Daryl, all the units I have seen have two wires, mine include. Yes one is positive & one for negative, my suggestion is to disconnect both wires from the magnet, generally there is a joiner outside of the backing plate so there is no need to remove the wheel & brake drum.

Then check the two wires from the van wiring, only one should be a positive ( Power ), check this with a test leadwith inbuilt light.

If both wires are positive then there is a fault in the wiring of the plugs

If this test is correct, then check the second wire, this has to be an earth, (or -). this can be done by connecting the test lead between the two wires , the test lead should light up. If this fails there is a problem with that earth wire, broken, disconnected, loose etc. In this situation it allows power to return back from the magnet & along this wire .

If you think the plugs are wired correct, you will have to trace all the wiring from the brakes back along the axles & to the chassis as there will be joiners where the wire splits & goes to each wheel. Sounds like a earth prob to me so all connections need to be checked.

I beleive that the wires from the magnets can go either ways.

Note, if its a joiner just the handling of the wires can at times make a loose connection work again, makes it hard some times to identify just which one is at fault. Bad earths are the cause of many problems.

Happy hunting; talk to you soon.

JC.

-- Edited by justcruisin01 on Monday 12th of November 2012 09:22:09 PM

Baz421 · Guru

Well said JC

Just looked at a brand new ALKO brake assembly, 2 green wires and I can't see a + or a - marking on the wires so it looks like polarity doesn't matter.

-- Edited by Baz421 on Monday 12th of November 2012 09:43:14 PM

Baz421 · Guru

Daryl

these show 2 wires + and return earth to tow vehicle.

http://www.alko.com.au/uploads/2008/12/Wiring-Diagram.jpg

http://www.championtrailers.com/Electric%20brake%20control%20wiring.pdf

Probably does matter which direction the current flows for magnets, one direction applies the reverse tries to un apply as this is how they are probably wound and fitted.

Quick tests. Did brakes work previously??? Try when connected to another vehicle (if possible) ???? Try these first is my suggestion if you cannot follow the Alko wiring diagram and test.

Cheers Baz

justcruisin01 · Guru

Baz421 wrote:
Well said JC

Thanks Baz, we had lunch with this couple last year, great guys so just have to try & help them out.

JC.

PeterD · Guru

DandS wrote:
I checked the power at the brake drums and notice that I get power at both the wires that run into each magnet (Alko).

What do you mean by this? Are you using a meter and measuring the voltage between each wire and the chassis? If you are and you are seeing the same voltage at each wire then you have problems.

One of those wires should have a positive voltage on it and the other should be near chassis potential. If the voltages are the same or close to being the same you have an earthing problem. You will have to find the disconnection in the earth wire that goes to one side of the magnet.

Note, in practical van setups, if you run the negative lead back to yout tugs starting battery, you will never see zero volts on the negative side of the brake magnet.

DandS · Senior Member

Thanks Baz, Jim & PeterD.

The info you supplied was a great help & very much appreciated.

This morning I started tracing and inspecting the wires and connections, the wiring had a few extra joins here and there.

I decided to remove all the wiring that goes from the trailer plug to the brakes & replaced with new wire and joiners.

Connected the plug to car and all working OK .

Once again, thanks to you for the info and advice. .

Had a good ending and a good day.

Regards

Daryl & Syl

-- Edited by DandS on Tuesday 13th of November 2012 03:17:18 PM (bad speller)

-- Edited by DandS on Tuesday 13th of November 2012 03:18:58 PM

Baz421 · Guru

Nice to see a good outcome at minimal cost.

justcruisin01 · Guru

DandS wrote:
Thanks Baz, Jim & PeterD.
The info you supplied was a great help & very much appreciated.
This morning I started tracing and inspecting the wires and connections, the wiring had a few extra joins here and there.
I decided to remove all the wiring that goes from the trailer plug to the brakes & replaced with new wire and joiners.
Connected the plug to car and all working OK .
Once again, thanks to you for the info and advice. .
Had a good ending and a good day.
Regards
Daryl & Syl

-- Edited by DandS on Tuesday 13th of November 2012 03:17:18 PM (bad speller)

-- Edited by DandS on Tuesday 13th of November 2012 03:18:58 PM

Daryl, you done well mate, & took the best attack as many times when there is old wiring that has been joined & messed up it is best to remove it & start again as this can be quicker than hunting down the problem area.

Next time we meet we will make time for a beer.

Cheers mate.

JC.

DandS · Senior Member

justcruisin01 wrote:
Daryl, you done well mate, & took the best attack as many times when there is old wiring that has been joined & messed up it is best to remove it & start again as this can be quicker than hunting down the problem area.

Next time we meet we will make time for a beer.

Cheers mate.

JC.
My shout Jim !!
Took me about an hour to re-wire, and $20 for new wire & connectors.
One has to question the expertise of the auto elec at the company I purchased the van from. He was adamant that the magnets only had one wire.
Thanks again!!
Daryl

justcruisin01 · Guru

DandS wrote:
justcruisin01 wrote:
Daryl, you done well mate, & took the best attack as many times when there is old wiring that has been joined & messed up it is best to remove it & start again as this can be quicker than hunting down the problem area.

Next time we meet we will make time for a beer.

Cheers mate.

JC.
My shout Jim !!
Took me about an hour to re-wire, and $20 for new wire & connectors.
One has to question the expertise of the auto elec at the company I purchased the van from. He was adamant that the magnets only had one wire.
Thanks again!!
Daryl

I would make a point of letting him know just how wrong he is & that his services are no longer required now or in the future. confuse confuse confuse

JC.

hagar · Veteran Member

All connections on trailer side of electric brakes should be soldered do not use joiners

justcruisin01 · Guru

hagar wrote:
All connections on trailer side of electric brakes should be soldered do not use joiners

I solder every wire connection that I make; but assemblers & sparkies take the quick way out by crimping knowing that they will gain more work at a later date. Dont think I could even count the amount of quick connect fittings that I have thrown away over the years. They are a problem further down the track & particualy if they are external.

JC.

Baz421 · Guru

If you solder wires make sure they are held in place and cannot vibrate as they can easily fail at the point where the solder finishes and the wire reverts to the copper strand if they are allowed to vibrate. Same principle that steel cracks right next to the weld.

Lived in the NT for 25 years and trailers (semi, box, boat, caravan -all of em) had same problems.

I generally solder as well if possible and accessible.

Cheers Baz

03_troopy · Guru

At the risk of igniting a soldering versus crimping battle, I thought I'd just add my 2c worth. As Baz mentioned, soldering has an inherent weakness at the point where the wicked solder ends and the strands of the wire begin. This is the most common place for soldered joints to fail due to vibration. Not to mention the fact that many people who who try to solder aren't very proficient in it and are like to make poor joints as well. Good solder joints should look clean and shiny when cooled and have a concave profile where the solder mates with the soldered piece. For most soldering of electrical components you should use 60/40 resin cored solder, definitely not the 50/50 acid core that seems to be popular with many auto elecs. The acid flux in this type of solder will corrode the wire over a period of time, and the corrosive effect will wick up the wire under the insulation and damage the wire for quite a distance from where the joint was made. Also solder is not suitable where heavy current carrying conductors are attached via a lug. The reason for this is that if the lug happens to come loose, the resultant heat generated by the the high resistance connection can cause the lug to heat up enough for the solder to melt and the conductor to fall out.

Crimping, when done with the correct tools, will give a much more mechanically sound joint in situation where vibration is a concern. A properly formed crimped connection will be just as electrically sound as a soldered joint, but it will give the added advantage of the strands of the conductor being supported at the point where they exit the lug or splice. This is why you find that 99% of joints in aircraft wiring are crimped and not soldered. The key is, using the correct size and type of lug/splice for the job, and the correct tool for the application. The old superchamp style crimpers sold in many outlets for between $5 an $10 are a waste of time, and a decent pair of ratchet style crimpers for insulated lugs will set you back about $50. For heavy conductors, you can get these done at an auto elec who has the proper hex type crimpers for the job.
This info is from my personal experience of around 30 years as an avionics technician, and the last few years working on anything from modifying games consoles using 30AWG to repairing industrial welding equipment of up to 600A output using up to 75mm CCA cable. And my current job as an auto elec building mine service utes and trucks and currently wiring up a blast hole drill rig similar to this one.

Here is an example of some very poor soldering I recently found in a vehicle which was done by "qualified" auto electrician. Incidentally, this same guy also used superchamp style crimpers and we had to replace every crimped terminal he had fitted.

crap soldering.jpg

jimricho · Guru

I agree with your views on crimp versus solder but I do confess to soldering Anderson plugs so that I can later re-use them if the need arises. I take care to use some heat shrink to provide some strain relief where the stress concentration occurs.

Unfortunately there seems to be a minority of auto sparkies that are, shall we say, less than professional in their standards. There are also some who are less than au fait with auxiliary/house battery system issues in caravans and motorhomes.

I hasten to add that many others are both professional and knowledgeable.

justcruisin01 · Guru

Troopy, that would have to be the worst bunch of wire connections that I have ever seen. If that person is called a professional then he should be removed from the trade. I can relate to what you are saying with breakages in soldered joints but the biggest problem with todays method of crimping by sparkies & handymen is the corrosion between terminal & wire when subjected to the elements.

I have always soldered all connections, including my own & have never had a breakage problem in many years of travelling this big land, including the rough stuff. I did in one accasion have a wire break off, that was a crimp, ( toyota factory) on the heavy alternator charge wire right at the alt. Guess it just goes to show that nothing is fail proof.

JC.

03_troopy · Guru

JC, a piece of dual walled (glue lined) heatshrink over the joints will keep out any adverse conditions. It would also help to support soldered joints as well. The funny thing is that I was an accredited High Reliability Hand Soldering Instructor (that is, soldering to aircraft maintenance quality standards), Yet I'd crimp rather than solder any joints in motor vehicles or or caravans any day. Even though in my current job we solder more often than not. Why? "because that's the way we do it" which you could read as... because I don't have a clue as to proper methods and techniques of crimping joints" Well all too often the same could be said for their soldering techniques too. Here are a couple more I cut out of two vehicles a few weeks back.

As you can see, these joints were made using a small butane torch which has overheated the joints and burnt the insulation. If you look closely at the top one, you can see that the joint has probably only 10% wetting (solder flow) between the 2 pieces of wire.

Nomad246 · Senior Member

Amazing pics of potential problems. I wonder why people claim to be experts and end up with a job like this

Thank you for sharing

klo7 · Newbie

One of the most important items when installing electric brake controllers is to use a circuit breaker instead of fuses.[ once a fuse blows you have no trailer brakes] Also I run an earth wire from the battery to the plug instead of relying on the body earth. I also run an active from the battery direct to the trailer plug. Many installers use the existing boot light feed for trailer power and earth only to body.

jimricho · Guru

Looks like that join in Troopy's post was soldered with a gas torch and not a soldering iron! Whoever did that should have stuck to their trade as a plumber or roof installer! I've soldered and sealed joins (as described in the same post) in wires going to a bait tank pump where the join was submerged in salt water and not had any problems with them.

Welcome to the forum klo7,

Yes, agree with your comments regarding the earth wire. (also the circuit breaker). Tekonsha is very particular in its instructions to run the controller's earthwire right to the battery terminal as well.

Banglabill · Member

You may alreday have the answer for this but YES you require two cables at each wheel for the magnet to work, it is a coil around an iron core to make a magnet when power is applied, it does not matter which way the hot wire is or the earth at the brakes, but it makes a difference at the other end of the circuit.

But the magnets in the brakes definatley require two cables, not a good idea just to run one wire and use the earth somewhere near the brake backing plates

Best regards

Banglabill