Guess there are 2 kinds of emulators? One that is the $25 gadget (lights only) and one that has a readout on the amp output?
Steve, with you on the getting it fixed.

Do you have a step-by-step checklist for an individual to perform by himself? To keep me from missing something?

Thanks again.....

Joe

 

Udate-----

Steve, I don't know how to check the amp load with my VOM--shows my electrical acumen... With the harnesses hooked up, I finally thought to listen at each wheel for magnet activation: the right front is not humming when the controller is pushed on at 10 setting. So, guess that is where one problem may be.
I'll be getting under to look that wheel over, but I don't have the socket to take the NevRLube spindle nut off to remove the hub. Prob gonna mean a trip to an RV shop.

None of the brakes 'hum' or 'activate' with the amount of noise I have heard on other trailer when checking them. Other 3 wheels are weak-sounding 'hums.'

Joe

 

no hum is no power at the wheel. Should be 3 amps at each wheel. So fix the power at that wheel is probably going to get you much closer to the weak brake issue.

 

Just walked in the door. Joe, does you meter have an amp setting? I am guessing you are using a meter that uses probes and alligators clips if I am lucky. It should have three plugs at the bottom. One when you are reading volts and resistance and one that is open for reading amps. Does it?

Listening is helpful, but it doesn't tell you how much, just that things are activating.

Steve

 

I read through the thread and one person hit on the grounding issue, but I don't think the correct question was asked.

Is there a hard ground wired across the 7-way trailer connection, or are you relying on the soft grounding of the hitch?

 

TexasRebel,
Everything is grounded thru the harness--normal fifth wheel setup.
Steve,
Have a Craftsman VOM and it is as you describe, except probes, not clips. And for listening--NO hum at the RF wheel.

 

10 or 20 listing for the amps?

Steve

 

10 amps in micro or milli amps. Do I need one that reads higher?

 

Crap, yeah, you need something to read at least 10 amps. That way, even if it blows the fuse in the meter, we would know all the magnets are on board.

What is the model number on your Craftsman meter.

Is there no one near you whom you can trust this kind of work? It is really basic stuff. I can walk you through it, but without a decent meter, you can't do it. So far you are doing well, but are you really sure you want to learn how to do this?

Steve

 

I think the VOM is 10a limited to 30 seconds max, for DC current. If I blow it, then I get a Fluke, eh?
Damn right I want to figure this out--have a friend going thru same thing with a GM and a HitchHiker. He had it worked on several times, no permanent results--kinda like mine, never knows when the brakes are gonna show up. But his is due partly to some melted wires that happened when the emerg cable pulled and it was wired wrong. Funny, same thing happened to another friend, with an Open Range--new. Accidentally pulled the cable out and had a meltdown--warranty work, tho and fixed ok.
At any rate, if you have the time and patience, I have the need.
If I thought I could drag both units over somewhere and they would be able to take only a day to do it, I would. But, can't let the truck go more than that.
Thanks.
Joe

 

The wires always melt when the breakaway pin is left out. It can only be out briefly as in an emergency before the wires will melt. They are much too small a gage to carry the brake amperage for long.

10 amps for 30 minutes is enough. I will get back to you.

Steve

 

It was SECONDS, not minutes. There is a warning about any longer than that.

If I need a VOM of better quality, will be glad to get one. And learn how to use it, maybe?

Thanks, Joe

 

The hardest thing here it figuring out how to do it with what you have on hand. This is not the way I would do it as I use a high-end clamp meter and it takes only minutes at most to do this.

First I want to develop a working hypothesis. Someone said earlier on that if the voltages and amp draws you posted earlier were correct, the problem is your trailer. I agree and want to verify the problem is on the trailer side of your seven pin cord on your trailer.

1. Verify your trailer battery is fully charged, that is more than say 12.5 volts. We are going to use that battery to power the trailer brakes. Make sure you truck is not plugged into your camper!

2. Find the junction box where your seven pin cord connects to your trailer and remove the cover. It is a metal box somewhere under the pin box (the part you connect to on your trailer).

3. In that box you will see where the blue lead from your seven pin cord and a lead from your break-away switch connected to the lead from the trailer brakes. Take off that wire nut and separate the lead to the trailer brakes from the other two leads.

4. Now you will have the two leads that feed the hot side of the trailer brakes and the lead to the trailer brakes. Since we do not have any load on the hot leads, we can pull the break-away pin without melting any wires as our circuit is open.

Pull the pin and, with your meter set on volts DC, put the red probe on the lead in the junction box from the break-away and the black probe on a good ground. Usually the junction box will suffice. You should see the same voltage you saw when you measured it at the battery.

We now have our power source for the magnets in the brakes.

5. Next we are going to measure the amp draw to the brakes. I would never do it this way in the field, but I think we can do this to save the fuse in your meter.

Take a regular 10 amp automotive fuse and touch one leg to the lead from the break away and the other leg to the lead feeding the trailer brakes. If the fuse blows we know we have more than a ten amp load on the fuse and thus more than 10 amps to the magnets.

If the fuse does not blow, we have a problem in the trailer brakes.

Read this over and see if it makes sense. Everyone else following along, please look over my shoulder and correct me if I make a mistake, It is much harder to me to tell someone how to do this than it is for me to do it.

Steve

 

Steve,
Separated the blue from the 2 black leads. Voltage across battery terminals is 12.70.
Voltage across the blue to ground with the pin pulled is 12.08. Is this a significant difference?
Sorry about the delay, sidetracked by honey-dos...
Joe

 

Should still be enough to power the magnets, but for so short a run and so large a drop, I would suspect the battery connection to the break-away may need attention.