Weird trailer brake problem

[Wayloncle]

I have a 2017 Chevy 2500 with integrated brake controller, my boat trailer is a Platinum with electric/hydraulic brakes.
I have noticed the lights aren’t working all the time, my 7way plug has a crack in it so I figured I’d just put a new one on. The ground wire was pulled out of the terminal inside the plug, so that was that problem. Still put the new plug on, all lights work fine, reached in the window and pulled the brake controller lever and heard the hydro pump run. Cool.

I got in the truck and pressed the pedal and didn’t hear the pump. So I checked and brake lights work with the pedal, just the brakes aren’t working with the pedal.

im assuming there are some sensors between the pedal/master cylinder and the brake controller that is not working

A quick interweb search didn’t find anything like this for a Chevy with integrated controller.

anyone had this problem or have an idea?

 

[AZMark]

Don’t brake controllers need to sense some inertia to apply the brakes?

Edit: so try driving it slowly, turn your brake adjustment up and see if you can feel them pull you to a stop so you know they’re working.

 

[dgfreeze]

@AZMark is onto what your "problem" likely is. If you get to cruising down the street, and try it again, I'm guessing you'll realize the trailer brakes are working just fine with the pedal. I don't like how they're set up, it makes diagnostics a lot more difficult, but that's how most OEM integrated brake controllers function.

 

[Wayloncle]

I know for my prodigy aftermarket controller I had on my old truck that’s how it worked, but with this electric over hydraulic system the pump normally runs when you apply the brake wether you are moving or not.
I’m pretty sure these integrated controllers use pressure from master cylinder or somewhere in the brake system, because I can normally sit at a red light and watch my brake controller output meter thing go higher as I press the pedal harder. Like it reads 0%-100%.

I cranked the controller up to 10 and it didn’t do anything by pedal in the gravel, using the controller it locked up at like 15%

 

[WV Hillbilly]

Built in controllers (factory OEM) units may or may not work with electric over hydraulic brakes depending on the brake actuator manufacturer. You will get three different results or levels of compatibility:
1. Doesn’t work at all
2. Works only when you manually apply the brakes on the controller on the dash
3. Works as intended

I don’t know who manufactured the axles but it sounds like you have result #2 from above.
There are a couple of things you can do to correct this.
Install an aftermarket controller that works with your actuator

install a new actuator

install an adapter to correct the problem

This all assumes the wiring on both the truck and the trailer are in working order.

I had a 2015 GMC that didn’t throw trailer problems (lights brakes disconnects) up in the driver information center (dic), it didn’t check them and it didn’t care. My 2022 GMC 2500 constantly monitors all trailer connections and throws information up and also puts the trailer under security when parked. So, if your 2017 throws information up in the dic and you are not seeing a problem when hooked up, I would doubt there is a problem in the truck.

here is a similar situation posted on etrailer about EOH on a 2017. If you can tell them what axles/brakes/actuator you have they can probably find a solution for you.

https://www.etrailer.com/question-439711.html

 

[Wayloncle]

Built in controllers (factory OEM) units may or may not work with electric over hydraulic brakes depending on the brake actuator manufacturer. You will get three different results or levels of compatibility:
1. Doesn’t work at all
2. Works only when you manually apply the brakes on the controller on the dash
3. Works as intended

I don’t know who manufactured the axles but it sounds like you have result #2 from above.
There are a couple of things you can do to correct this.
Install an aftermarket controller that works with your actuator

install a new actuator

install an adapter to correct the problem

This all assumes the wiring on both the truck and the trailer are in working order.

I had a 2015 GMC that didn’t throw trailer problems (lights brakes disconnects) up in the driver information center (dic), it didn’t check them and it didn’t care. My 2022 GMC 2500 constantly monitors all trailer connections and throws information up and also puts the trailer under security when parked. So, if your 2017 throws information up in the dic and you are not seeing a problem when hooked up, I would doubt there is a problem in the truck.

here is a similar situation posted on etrailer about EOH on a 2017. If you can tell them what axles/brakes/actuator you have they can probably find a solution for you.

https://www.etrailer.com/question-439711.html

My truck has worked with the trailer in the past, My wife’s ‘21 Tahoe with all the monitoring would work for a minute, go through all the light test and everything but after traveling for a bit it would stop recognizing the trailer, the trailer didn’t pull enough electrical resistance, I added a pigtail with resistors and that fixed it for that.

im going out today and hook up to my fifth wheel and see if the brakes work with that, they are electric, but at least I can tell if my controller is sending brake signal when I push the pedal. Depending on those results I’ll hook the Tahoe to the boat and see what it does.

 

[WV Hillbilly]

My truck has worked with the trailer in the past, My wife’s ‘21 Tahoe with all the monitoring would work for a minute, go through all the light test and everything but after traveling for a bit it would stop recognizing the trailer, the trailer didn’t pull enough electrical resistance, I added a pigtail with resistors and that fixed it for that.

im going out today and hook up to my fifth wheel and see if the brakes work with that, they are electric, but at least I can tell if my controller is sending brake signal when I push the pedal. Depending on those results I’ll hook the Tahoe to the boat and see what it does.

Had similar problems with the backup lights on a couple of my trailers with the light test working but throwing up a “check backup lights” after a while on the 2022. Lights still work although the truck thinks they may not be since they don’t pull much juice.

I am going to follow this since I am look at a Big Tex gooseneck with EOH brakes. I think they use Dexter axles and actuators…. Which may seem to be a problem…

I think you are on the right track for running this down. Let me know if I can help, I have a very good GMC dealership in town and am good friends with the service manager and owner. We may be able to pull corporate in on this if needed.

 

[WV Hillbilly]

One more bit of info…

https://www.etrailer.com/question-153300.html

 

[FSH 210 Sport]

When the integrated controllers first came out, the controller will not work unless the truck is in motion, and, once the truck slows down trailer braking decreases, they also work in concert with the anti lock braking system, E.G. the trailer braking pulls back once the anti locks activate. However, the manual override still works.

Have you tried it yet while you are moving to see if it works right now?

 

[Maslin]

Our '23 Tundra has 3 settings for trailer brake mode on each trailer "profile". The 190 trailer has surge brakes, so no problem there, but I'm interested to see how it handles the LED lights and reverse lock out.

I've been tempted to just drive around with the boat for a while, not sure the wife is up for boating in 20* and ice.

 

[Wayloncle]

@WV Hillbilly you pointed me in the correct direction, after reading that the hydra star actuators didn’t work with all controllers made me realize I couldn’t remember what brand mine was. I went out and connected to my 5th wheel, worked like it should, went to the boat and and saw hydraStar.

I sent an email to their tech support about 20 minutes ago, a tech called me about 5 minutes ago, he said 2018 time frame is when the Chevy controllers started working with their EOH actuators. He said there was an adapter I could wire in and it’ll start working, he described how to wire it in and gave me a part number. I asked if it was just a resistor, he said “yep, just a 2ohm resistor”. I have a few that I bought to wire into the lighting to make the Tahoe work with this trailer then I found a pig tail and just bought that, so I’ll just use the resistor I already have.

So, thinking back…the trailer brakes have never worked with my truck, with my 2500 Duramax I never noticed, and sitting in the driver seat you can’t hear the pump. I’ve always used the manual controller lever to check if the brakes were connected and working.

anyway, thanks for y’all’s thoughts and help. And I’m glad there isn’t something wrong with my truck

 

[FSH 210 Sport]

Let us know the final result please!

 

[Wayloncle]

For anyone interested, this is the resistor installed pig tail that I use with our ‘21 Tahoe.

I’m going to see if it makes the brakes work with my truck before I wire in a resistor, I’ve never used it with my truck. Ill
Post back with results.

CURT 57003 LED-Compatible 7-Way RV Blade Vehicle-Side Trailer Wiring Adapter Amazon.com

 

[FSH 210 Sport]

Don’t brake controllers need to sense some inertia to apply the brakes?

Edit: so try driving it slowly, turn your brake adjustment up and see if you can feel them pull you to a stop so you know they’re working.

The pendulum style after market ones do.

The newer integrated ones use a transducer on the master cylinder to convert brake line pressure into a variable output device to control activation, but the operator still sets the gain.

Wayyyy back when, the K&H brake controllers used an add one transducer for trailer brake activators.

 

[WV Hillbilly]

@WV Hillbilly you pointed me in the correct direction, after reading that the hydra star actuators didn’t work with all controllers made me realize I couldn’t remember what brand mine was. I went out and connected to my 5th wheel, worked like it should, went to the boat and and saw hydraStar.

I sent an email to their tech support about 20 minutes ago, a tech called me about 5 minutes ago, he said 2018 time frame is when the Chevy controllers started working with their EOH actuators. He said there was an adapter I could wire in and it’ll start working, he described how to wire it in and gave me a part number. I asked if it was just a resistor, he said “yep, just a 2ohm resistor”. I have a few that I bought to wire into the lighting to make the Tahoe work with this trailer then I found a pig tail and just bought that, so I’ll just use the resistor I already have.

So, thinking back…the trailer brakes have never worked with my truck, with my 2500 Duramax I never noticed, and sitting in the driver seat you can’t hear the pump. I’ve always used the manual controller lever to check if the brakes were connected and working.

anyway, thanks for y’all’s thoughts and help. And I’m glad there isn’t something wrong with my truck

I hope that fixes it (and I have no reason to believe it won’t since you talked to tech support).
I haven’t had max weight behind my 2022 Denali Duramax but I can tell you that 10k behind that truck is a mirror checker just to make sure it’s still back there. Amazing what an 8800 pound truck will make disappear while towing with it.

 

[drewkaree]

I've been tempted to just drive around with the boat for a while, not sure the wife is up for boating in 20* and ice.

*adds this theory to the memory bank for future reference and use

 

[Wayloncle]

Update on testing the pig tail, it doesn’t work for the brakes.
I couldn’t find any info on what size resistors are in the pigtail so I tested it, it only has 1 ohm. The HydraStar tech I spoke with said their adapter is a 2 ohm resistor (which they sell for like $185. So I’ll wire in the $3 6ohm resistor that I have

 

[AZMark]

Update on testing the pig tail, it doesn’t work for the brakes.
I couldn’t find any info on what size resistors are in the pigtail so I tested it, it only has 1 ohm. The HydraStar tech I spoke with said their adapter is a 2 ohm resistor (which they sell for like $185. So I’ll wire in the $3 6ohm resistor that I have

RIP Radio Shack

 

[Wayloncle]

Final outcome for this. I tried the 6ohm resistor that I had, didn’t work at all, ordered 2ohm resistors like the tech told me it needed and he said the adapter they sell is 2ohm. It didn’t work at all either, so I broke down and ordered their $140 adapter, it reads 1.6ohm but maybe there is more to it than a resistor in there, it’s a sealed aluminum block about 6” long by 4” wide. I finally installed it this morning and it works like it should.