Troubleshooting Surge Brakes Locking up When in Reverse

Updated 11/08/2025 | Published 12/15/2015

Products Featured in This Question

Demco Hydraulic Drum Brake Assembly - Single Servo - Galvanized - 10" - Right Hand - 3,500 lbs

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$76.98

Replacement Solenoid Valve for Dexter Brake Actuators with Reverse Lockouts

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Solenoid Shield for Dexter Model 60 Trailer Brake Actuators - Zinc

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Question:

surge brakes lock in reverse and will not apply going forward

asked by: Bill D

Expert Reply:

With surge brakes, you have a brake actuator applying the needed pressure to the brakes but to be able to back up you will need to have a manual lockout or an electric lockout solenoid, like # T4748800, which will close when you shift the vehicle into reverse, allowing the trailer to be backed up.

You may also need a solenoid cover like the Titan # T4835800183, depending on what brake actuator you currently have.

Typically surge brakes are found on boat trailers, and commonly the trailer ends up being to light after the boat has been launched for the brakes to actuate properly when going forward. The fact that the brakes lock up in reverse makes me think they work, but a change in the weight of the trailer can prevent them from working properly under normal operation. If you could provide me with some more information about your setup, I would be more than happy to further troubleshoot this issue with you.

expert reply by: Jackie C

Keith M.

9/17/2024

Hi. I just returned from a 150 roundtrip pulling my Shorelander boat trailer. When I tried to back up my trailer into my driveway, the surge brakes locked up and I had to use the mechanical bypass clip to get the rig to back up. The electrical connection is plugged in and I do have full lights to the trailer, but apparently the electrical surge bypass isn't working. Does it sound like the reverse solenoid needs to be replaced? Any other ideas?

Jon G.

9/17/2024

@KeithM It could be that, yes. The best place to start though is making sure the reverse circuit on your vehicle 5-Way is sending a signal. Then you can use a circuit tester # PTW2992 to verify that power is actually getting to the actuator. If you have power getting to it then yes, I would say the electrical bypass isn't working and you'd need to replace the solenoid. Let me know what coupler you have and I can see if we have a replacement solenoid for you (granted that we carry the brand).

Lenny

9/23/2025

I have a titan model 6 actuator on my boat trailer. Can this unit be manually override when backing up? Surge brakes engage and will not allow me to back up.

Jesse M.

9/23/2025

@Lenny You would need to add an electric lockout solenoid like part # DM11993 to allow backing up without locking up the brakes.

Lenny

9/24/2025

@JesseM I understand but what if solenoid quits? is there a way to temp. override until new one is installed?

Jesse M.

9/24/2025

@Lenny If the solenoid quits it will need to be replaced. There would not be a way to manually lock it out.

Michael T.

11/8/2025

I naught a new boat and I had no problem with reverse putting the boat in the water but when I took the boat out of the water and took it to my house and put it in reverse the brake on the trailer was locked up.