Electric Over Hydraulic Brakes Don't Work w/Brake Pedal on Newer GM Trucks w/OEM Brake Controller
Updated 10/28/2025 | Published 02/17/2016
Products Featured in This Question
Question:
My company has a Walton two axle heavy duty trailer with electronic over hydraulic brakes. Most of our trucks are newer Chevys or GMCs. After electrical testing I found the actuater on the trailer to be faulty. I replaced the actuater. The truck can sense the trailer, but I can only engage the trailer brakes using the manual slide on the brake controller in the cab. The brake pedal does not engage the trailer brakes. All the wiring is as it should be. Ive read that some trucks had problems with E/H brakes and thier factory installed tow packages, but that had to do with the truck not sensing the trailer. If you have any ideas about why the trailer brakes only engage with the manual lever and not the brake pedal I would very much like to hear them.
asked by: Richard
Expert Reply:
Like you said, many factory integrated brake controllers will not work well with electric over hydraulic trailer braking systems. Some of the newer versions of these controllers now have an electric over hydraulic mode. Check to see if any of your trucks have this mode and, if they do, if the braking starts working with the pedal.
Otherwise there are a couple of solutions to solve this issue. First, there may be an adapter that will allow the factory controllers to work but it depends on the actuator being used. For example, there isn't an adapter for the Dexter actuators such as # K71-651. But there is one for the Hydrastar # HBA16; adapter # HBA-CAM.
The other option is to switch all of the trucks to aftermarket brake controllers that are compatible with electric over hydraulic braking systems such as the P2 # 90885 or the P3 # 90195. I have included a link to a help article on installing an aftermarket controller on a 2007 to 2013 Chevy or GMC truck that has the factory integrated controller that should also help.
Marc S.
10/5/2025
I currently have a 2024 GMC 2500 6.6L gas Long bed with OEM puck system. Will be moving into a larger 5th wheel rig and considering changing from drum to disk breaks. Not clear but sounds like i may have issues with my OME trailer brake. Can you provide information that will help me navigate this pathway to give better stopping performance. Thank you in advance Marc
Nick S.
10/6/2025
Nick S.
10/6/2025
Mark S.
10/27/2025
I have a 2024 Chevy 6500 dump with the same problem as everyone else, I got the module from etrailer for my trailer and the Chevy still doesn’t work, I have a Hopkins 47235T I bought for my other truck, my question is how to hook it up in my 2024, should I run a new wire to the trailer in the socket on the truck? Chevy dealer is useless I had it there 3 times and they keep telling me that the trailer simulator says it’s good but it’s not, I’m tired of driving a hour each way to the deal so any help that you can give me would be greatly appreciated, thank you in advance, Mark ps it’s a dexter actuator for my electric over hydraulic brakes on a 12.5 ton tag along
Jameson C.
10/27/2025
Jameson C.
10/28/2025
Product Page this Question was Asked From
Dexter DX Series Electric Over Hydraulic Brake Actuator for Disc Brakes - 1,600 psi
- Brake Actuator
- Electric-Hydraulic Brake Actuator
- Boat Trailer
- Travel Trailer
- Disc Brakes
- Dexter
more information >
Featured Help Information
Instructions
Miscellaneous Media
Continue Researching
- Shop: Brake Controller
- Search Results: deemaxx trailer brakes
- Shop: Hydrastar Electric Over Hydraulic Actuator Adapter Module for Ford and Chevy Brake Controllers
- Shop: Hydrastar Electric Over Hydraulic Actuator for Disc Brakes - 1,600 psi
- Shop: Adapter Module for BrakeRite Electric Over Hydraulic Actuator - OE Ford, GM Brake Controllers
- Search Results: brake actuator
- Search Results: trailer brakes
- Search Results: electric over hydraulic trailer brake controller
- Q&A: How Wide is the Curt Weight Distribution Shank C17132?
- Shop: DeeMaxx Disc Brake Kit w/ Actuator for Tandem Axle Trailers - 13" Hub/Rotor - 8 on 6-1/2 - 7K
- Shop: Deutsche Hydrapro CAM Adapter Module for Dexter and Hydrastar Electric Over Hydraulic Actuators
- Search Results: hydraulic brake line kit
- Shop: Dexter DX Series Electric Over Hydraulic Brake Actuator for Disc Brakes - 1,600 psi
- Search Results: k71~180
- Shop: DeeMaxx Alpha G1600 Electric Over Hydraulic Actuator for Disc Brakes - 1,600 psi
- Video: What to Know About the Adapter Module for BrakeRite Electric Over Hydraulic Actuator
- Video: Hydrastar Brake Actuator HBA-CAM Review
- Search Results: morryde pin box parts
- Q&A: Recommendation for Towing Trailer with Electric Over Hydraulic Brakes with Four Chevy Silverados
- Article: Trailer Wiring Diagrams
- Q&A: Electric Over Hydraulic Adapter Module For a 2024 Chevrolet Silverado 2500HD
- Video: HydraStar Electric Over Hydraulic Disc Brake Actuator Installation
- Video: Review of Stillwell NeXgen Cube Hydraulic Manifold - ST58FR
- Q&A: Looking for Replacement Actuator/Coupler for 2007 Karavan Boat Trailer
- Q&A: Electric Over Hydraulic Module For OEM Brake Controller On 2017 GMC Sierra 3500
- Video: HydraStar Electric Over Hydraulic Disc Brake Actuator Installation - 2017 Grand Design Solitude Fift
- Q&A: Is the HydraStar # HBA-CAM Adapter Compatible with a HydraStar with Serial Number 310837
- Article: Aftermarket Brake Control Wiring for 07-13 GM Full-Size Truck with Factory-Integrated Brake Control
- Video: Review of DeeMaxx Rubber Hydraulic Brake Line 18 Inch - DE22WR
- Article: Wiring Trailer Lights with a 4-Way Plug (It's Easier Than You Think)
on Brake Actuator
John K.
6/10/2024
I am converting my boat trail to electric over hydraulic. Towing @5500 lbs. I have a 2016 chevy colorado diesel with an oem brake controller on the dash. I was looking at the dexter dx and hydrastar systems. It sounds like the hydrastar will work with the HBA-CAM adapter but the dexter may not and there is no adapter available. Does that sound accurate?