I have a 2005 Manning tri-axel trailer under my 32' Sunsation and I am have issues with the brakes, when I went to put the boat away for the season I noticed the hydraulic surge brakes would not release so I put a C-Clamp on the slide and put it away for the winter. This spring had the 7-way adapter on the truck replaced and bought a new adapter, they still are partially engaged and at times will not release to back up the boat. I can wiggle the adapter and sometimes I can get the brakes to release. I am out of ideas anyone have any suggestions?

You have a bad ground or bad connection to the lock out solenoid.

Or a bad solenoid........make sure you reverse lights work on your truck...........as said check ground...............

whoever came out with the electric lock out deal on the tilton units should be shot...my .02

It's very common for the electronic solenoid for the reverse lockout to go bad. They are flowing corrosive fluid, so it happens. It's an easy swap out; and solid plan to have a spare with you on trips.
As stated, make sure you are getting power to that pin on the connector and all the way to the solenoid when the truck is in reverse.

https://www.etrailer.com/Accessories...co/DM5837.html

https://www.etrailer.com/Accessories.../T4748800.html

https://www.etrailer.com/Accessories...o/DM11993.html

https://www.amazon.com/Replacement-S...verse+solenoid

https://www.amazon.com/UFP-Electric-...verse+solenoid

https://www.amazon.com/Tie-Down-Engi...verse+solenoid

Ditto, I have had a solenoid go bad. The fluid abosorbs water and corrodes them.

UPDATE....it was solenoid valve that went bad picked one up on e-trailer for $32.00 and problem solved!

Dot 5 brake fluid does not absorb water, however, it's important to make sure it's compatible with your hardware

Just a note: dot 5 is not compatible with dot 3 or 4.

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