Troubleshooting Weak Trailer Brakes When 2023 Ram 3500 Brake Controller is at Full Power

Updated 06/19/2024 | Published 03/19/2023

Question:

Hi, I have Ram 3500, 2023 model. I pulling a 36 foot gooseneck. It has tandem duel axles ,Dexter 10K HD. I’m replacing the worn brakes and bearings. Previously when I applied the brakes or used the factory install manual trailer brake control I would feel very low brake resistance. So I decided to replace all the 4 brake assembly’s and all the bearings. Test the voltage at the brakes , with no magnets connected I only get 7.5 volts with the gain set to plus 10 and the brake pedal all the way applied , reading on dash show 100 applied . Is this enough voltage for the brake magnets to apply completely? I also ordered a new brake away kit from y’all that will be replacing soon. At the 7 way connecter I have 11.5 volts without the trailer cord connected at the box . No truck fuses blown . But the voltage drops to 7.5 when connected.. I have inspected all the wiring under the trailer frame and do not see and brakes or frayed wires. So I’m wondering if this voltage reading is normal? Maybe I’m over thinking this too much. But the brakes still seem light. But the brake in is not complete yet either . What are your thoughts ? And thoughts on the voltage drop?

asked by: Edward M

Helpful Expert Reply:

You will naturally see some voltage drop from the brake controller all the way back to your trailer brakes, but what you're describing sounds like a bad ground somewhere. What you need to do is check the grounds related to the trailer brakes and make sure they are securely connected to a clean, bare-metal surface.

Since the truck is brand new and the problem doesn't seem to happen until the trailer is connected, the best place to start troubleshooting is on the trailer. If all of the grounds seem to look good then be sure to remove the trailer 7-Way plug and check the connections inside of there as well. It would be good to add some Dielectric Grease # 11755 inside the connector to help protect against corrosion.

Let me know if you're still having issues and I'd be happy to help further assist!

expert reply by: Jon G

Luiz P.

5/6/2024

Hi everyone I bough a Hydrastar Electric Over Hydraulic Actuator for Drum Brakes - 1,200 psi I have the same problem mentioned by the consumer named Edward M: Troubleshooting Weak Trailer Brakes When 2023 Ram 3500 Brake Controller is at Full Power. Could you give me Edward M's contact details to find out how he solved the problem of low energy in the trailer's brake line. I appreciate your help Tks Luiz Pereira

Jon G.

5/6/2024

@LuizP If Edward M sees the comments he is more than welcome to respond, but we won't be sharing contact information. Have you tried the solution that I provided?

Luiz P.

5/6/2024

Hi Jon yes, I tested your solutions and it worked, I got 9.3 volts on the brake and now it's great Thank you

Jon G.

5/6/2024

@LuizP Awesome, glad to hear everything is now working out for you!

Jeff D.

5/12/2024

Jon, I also have a 2023 Ram 3500 and am experiencing the same problem with low voltage when testing (weak brakes). It has been driving me crazy trying to figure out what is going on. I finally discovered that RAM has speed sensitive controllers. Under 35 mph the controller will only allow a max of 7.5 - 8.0 volts. Above 35 you get full voltage. Apparently they did this to work with their abs system in the truck. This is a really bad design because you get little to no brakes in slower stop and go traffic. The solution is to switch to an aftermarket controller.

Jon G.

5/13/2024

@JeffD Thanks for the insight! If you haven't replaced your factory controller yet, I recommend checking out the Redarc Tow-Pro Liberty # RED24FR which can be installed virtually anywhere in your cab and connects to your vehicle using the Plug-and-Play Wiring Kit # 331-TPH-020. Please note that you may need to have your vehicle computer flashed at a dealership in order for the aftermarket controller to work.