Troubleshooting the Hydrastar Electric Over Hydraulic Actuator w/ a GMC Factory Brake Controller
Updated 12/22/2025 | Published 10/22/2024 >
Products Featured in This Question
Question:
I have a 2020 GMC 3500HD with integrated brake controller. I am towing a 2023 Riverstone Legacy 5th Wheel with Hydrastar HBA-16 disk brake actuator. Everything works fine most of the time, however while towing I will suddenly, intermittently get a message on the dash that says service trailer wiring, resulting in loss of brakes. Trailer lights continue to work fine. Over time, the error clears and I have trailer brakes again. I have not been able to figure out what conditions bring this error on. It can be a cloudy day or sunny day. The video and description of this adapter states for GM vehicles to present, but I see the reference that 2018 does not need it. Do you think this adapter would resolve my issue or has GM resolved the issue since and my problem is something different? I also have 600w of solar and 4 100ah lithium batteries. I did read something that maybe the truck brake controller is checking the trailer battery voltage causing the error. Any help would be much appreciated. Thank you
asked by: David M
Helpful Expert Reply:
Hey David! It sounds like your factory controller isn't communicating reliably with the Hydrastar Electric Over Hydraulic Actuator for Disc Brakes item # HBA16. Even though the item # HBA16 says it's compatible with your 2020 GMC's factory brake controller It is advised if you're having the issues you're describing to use the Hydrastar Electric Over Hydraulic Actuator Adapter Module item # HBA-CAM.
Product Page this Question was Asked From
Hydrastar Electric Over Hydraulic Actuator Adapter Module for Ford and Chevy Brake Controllers
- Accessories and Parts
- Brake Actuator
- Disc Brakes
- Hydraulic Drum Brakes
- Adapters
- Hydrastar
more information >
Continue Researching
- Search Results: 9 pin trailer plug
- Search Results: trailer light pigtail
- Video: Review of Hydrastar Actuator Adapter Module for GM Brake Controller - HYD29ZR
- Shop: Hydrastar Electric Over Hydraulic Actuator Adapter Module for GM Brake Controllers
- Shop: Hydrastar Electric Over Hydraulic Actuator Adapter Module for Ford and Chevy Brake Controllers
- Shop: Replacement Gear Pack for Lippert RV Slide-outs -2"x3" or 3"x3" Arms - Standard
- Shop: Replacement Gear Pack for Lippert RV Slide-outs w/ 2" x 2" Arm - No Roll Pin Assembly
- Video: Replacement Rubber Compression Bumper for MORryde Pin Boxes Feature Review
- Video: Replacement Gear Pack for Lippert RV Slide-outs -2"x3" or 3"x3" Arms Review
- Q&A: How To Install HBA-CAM Hydrastar Adapter
- Q&A: Can Integrated Brake Controller of 2024 GMC Sierra 3500 Work with Hydrastar Actuator for Keystone
- Q&A: Determining The Correct Replacement Slide Out Gear Packs For A 2010 Dutchmen Grand Junction
- Shop: etrailer Trailer Wiring 7-Way Upgrade Kit w/ Junction Box and RV Style Connector
- Shop: Replacement Rubber Compression Bumper for MORryde Pin Boxes
- Shop: Replacement Gear Pack for Lippert RV Slide-outs w/2-1/2" x 2-1/2" Arms - Heavy Duty
- Video: Checking Out the Replacement Gear Pack for Lippert RV Slide-outs w/ 2" x 2" Arm
- Video: Hydrastar Brake Actuator HBA-CAM Review
- Video: HydraStar Electric Over Hydraulic Disc Brake Actuator Installation
- Q&A: Wire Diagram for Installing a Voyager Brake Controller on a 2002 Ford F-250
- Q&A: Electric Over Hydraulic Adapter Module For a 2024 Chevrolet Silverado 2500HD
- Video: Setting up the 12V PWM Filter for RV Backup Camera Systems on a 2021 Thor Coleman Motorhome
- Q&A: Troubleshooting Lack Of Brake Controller Output With A 2025 Chevy Silverado 3500
- Q&A: Troubleshooting Signal Issues With A Furrion Vision S Camera System And Chevy Silverado
- Search Results: hitch pins and clips
- Search Results: hydrastar brake actuator
- Shop: Brake Controller
- Shop: Trailer Wiring
- Article: Trailer Wiring Diagrams
- Search Results: pigtail wiring harness
- Search Results: dexter brake actuator


Jerred H.
12/22/2025
Hey David, how did things go after adding the Hydrastar adapter module to your GMC’s brake controller setup? Did it clear up the intermittent “service trailer wiring” error you were seeing? Your update could make it easier for others towing with similar Hydrastar systems.