Trailer Brake Expert Needed

[UnlimitedMatt]

Is anyone here a trailer brake expert? I have some questions that I need help with.

I picked up a 23 foot 2005 KZ Coyote travel trailer last weekend, and I don't think the brakes work at all. My wife's cousin was the original owner and is who I bought it from. We have a good relationship with him, and he was very thorough on telling me all the known issues. The bad part is that he did absolutely zero maintenance on the camper, he only replaced the tires because he had a blowout on the highway. The camper only has approximately 5,000 miles on it. I haven't weighed it yet but my research says it weighs 4800 pounds.

Here is what I know:
My truck has a tow package and is pre-wired for a brake controller.
Last week I installed a Hopkins Insight controller.
When I hooked up the trailer to the truck everything worked as designed, except for the brakes.
When I turned up the controller and used the manual slide, nothing happens as far as the brakes go, but the brake lights do light up. I was expecting full lock up of the trailer brakes. It also will not hold the truck at a stop using the manual slide.
I checked the brake wire on the trailer (after the 7 wire plug, but before the axles) I get a zero reading on my volt meter until the brakes on the truck are applied. At that point I got a 1.5 volt reading (or something like that).

I'm trying to figure out what to do next. I'm hoping that the shoes just need adjusted, but I fully expect to replace everything.

I'm hoping for some quick and easy fix as I'm planning to use the camper a lot in July.

Any ideas?

 

[ThatGrimmJeeper]

I'm not an expert.

However, 1.5 volts sounds low. I know most brake controllers are progressive. They start low and ramp up over time. Does it stay at 1.5 volts or does it go up?

 

[UnlimitedMatt]

I will have to check it tomorrow. If I remember correctly it started out lower and progressively went up to 1.5.

You'll have to forgive me, at the time I was testing, I was in 90° + heat in the parking lot of El Pollo Loco in Tracy California. And my impatient 18 year old daughter was 'helping' me. Lol.

 

[SteveT]

The brakes on my popup have never worked, although everything appears to be there, and from looking at the pads, there is evidence that they've worked in the past. They seem to be inertia activated. A magnet swings on a pivotto energize. If I manually push that pivot forward, the shoes move out. I really only looked at the briefly while repack the bearings. I also can't seem to get twelve volts to the trailer through the plug, to run the fridge while towing.

Figger out yours, then you can come figger out mine.

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[old_man]

Have you pulled the drums off to see what it looks like inside?

First off, the most likely thing would be a busted wire somewhere. Think of it this way, if a wire to a wheel is busted, only that wheel will be affected. So you can rule out wiring after the split to each wheel unless the brakes have been physically trashed. Remember that there isn't a single wire to each wheel, there is also a ground wire. Many people wire a trailer expecting the ground to be completed via the hitch ball. That is not a good idea. Check continuity all the way from the controller to the wheel magnet on both the power and ground wires. That is why I have a 20+ foot meter wire with a clip.

 

[trippled]

Is the gain up on the controller? Sounds like it's way down. I use a test light at the pin on the trailer connector, vehicle side. It should start to light up gradually as you press the brake, of you have the gain to max. Some controllers will not turn the brakes on if it doesn't detect a trailer. If it's all good and still no brakes, problem is in the trailer, either wiring or ebrakes need adjusted or backing plates replaced.

 

[UnlimitedMatt]

Thanks for the tips so far!

For a quick test of my controller, I plan to hook up to a friend's trailer that we know the brakes are functioning properly. If that works, I will focus on my trailer. I'll start with verifying the ground as this very well could be the issue. When the po had a blowout on the interstate, the tire came apart and did some damage to the wheel well and surrounding area. If the ground for both axles is in one place, in that area, it may have been destroyed.

I'll update with my test results.

 

[ThatGrimmJeeper]

It doesn't hurt to ground to the trailer body as long as the ground wire from the plug also goes to the trailer body (and you have full conductivity between the two points).

Still, wire is cheap so why not just wire it straight from the plug to the brakes?

 

[old_man]

Thanks for the tips so far!

For a quick test of my controller, I plan to hook up to a friend's trailer that we know the brakes are functioning properly. If that works, I will focus on my trailer. I'll start with verifying the ground as this very well could be the issue. When the po had a blowout on the interstate, the tire came apart and did some damage to the wheel well and surrounding area. If the ground for both axles is in one place, in that area, it may have been destroyed.

I'll update with my test results.

Good common sense troubleshooting.:cheers:

 

[UnlimitedMatt]

Update: Made testing progress. My controller would not activate my friends trailer brakes, meaning the problem is my truck/controller.

I started troubleshooting connections at the controller and I believe I found my issue.

Before the flaming starts, let me say that I am no wiring expert. I know about as much of automotive wiring as a professional has forgotten.

Anyway, when I installed my controller last week, I didn't like that a little red LED inside of the controller was always on regardless of the key position. In my research I found this was normal, but it bothered me. So in my infinite wisdom, I decided to put a rocker switch in line on the power wire going into the controller. It worked as I planned, I could turn off the controller (the annoying red light) when I was not towing. I thought that the controller would not be too much of a power draw for the switch. But it seemed to act as a bottleneck. When I removed the switch, the slide on the controller sent varying amounts of power to the brake output wire.

Since I liked the idea of having a 'master' switch, I reinstalled the switch. But now the switch energizes a 40 amp relay to control the power to the controller.

Does anyone see an issue with this?

The real test will be tomorrow evening when I hook up to my trailer to see what happens. Fingers crossed!

 

[ThatGrimmJeeper]

In theory, the switch shouldn't restrict the controller. But a relay isn't a terrible thing to have in line.

 

[time2getdirty]

And to think you are my master electricians for all things zappy....

 

[UnlimitedMatt]

Victory! Well, almost...

On Saturday the trailer brakes work perfectly. The switch/relay seemed to do the trick. Fast forward to Sunday night, the switch lights up but no power to the controller. Something in the relay quit. So I once again bypass the switch/relay and everything works as designed.

Now I have to decide if I want to figure out why it stopped and replace the relay or deal with the annoying red LED. Decisions, decisions.

 

[SteveT]

Little square of black duct tape....?

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[time2getdirty]

Look at the time you spent to install your LED light bar on the front, another LED but this time you don't want it?! I don't get it.

 

[UnlimitedMatt]

Look at the time you spent to install your LED light bar on the front, another LED but this time you don't want it?! I don't get it.

You hush!

Good idea Mr T. But if I leave the truck sitting for 18 months and the little red light kills my battery, how do I use the tape to start the truck?:dunno

 

[Hypoid]

You hush!

Good idea Mr T. But if I leave the truck sitting for 18 months and the little red light kills my battery, how do I use the tape to start the truck?:dunno

Use the tape to secure the solar battery tender to your truck's roof for the next "year-and-a-half"... or tape a note to the windshield that you disconnected the battery "a year-and-a-half" ago. :twak:

 

[SteveT]

Drive a MANual transmission, ya know, like a man, and park on a hill.

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[time2getdirty]

I am confused, when do you plan to leave this truck alone for 18 months? How much power does one little LED use?

 

[trippled]

Yea in 18 mo that battery is dead either way! That led probably has less draw than the radio's keep alive memory