Dexter Reverse Lockout Solenoid K68-539-00 for Boat Trailer Disc and Drum Brakes

The Dexter Reverse Lockout Solenoid (K68-539-00) is installed at the brake actuator on a boat trailer to allow normal backing up without engaging the trailer's surge brakes. It is intended for actuators that do not already have a built-in reverse lockout lever or switch. Once wired in, the solenoid disengages the brake actuator's hydraulic function while the tow vehicle is in reverse, then automatically restores normal braking when driving forward again. This makes it a straightforward add-on for trailer owners whose actuator lacks a mechanical lockout mechanism.

The solenoid is a 12 volt electrical component that connects into the trailer's reverse-light circuit and the brake actuator. It is compatible with disc brake actuators, which require a reverse lockout device, and can also be used on drum brake setups. The housing has a painted exterior finish for corrosion resistance in a marine trailer environment.

Specifications

• Brand: Dexter
• Manufacturer Part Number: K68-539-00
• Category: Boat Trailer Brakes
• Function: Reverse lockout solenoid for brake actuator
• Voltage: 12 Volts
• Compatible Brake Types: Disc brakes (required); also usable on drum brakes
• Dimensions: 7 x 4.75 x 2 inches
• Weight: 0.58 pounds
• Exterior Finish: Painted
• UPC: 876983010073

Replaces (OEM)

• 81103

Frequently Asked Questions

What does the Dexter K68-539-00 reverse lockout solenoid do? It disengages a trailer's brake actuator while backing up, so the surge brakes do not drag or lock while the tow vehicle is in reverse, then restores normal braking when moving forward again.

Do I need this solenoid if my actuator already has a reverse lockout lever? No. The K68-539-00 is meant for actuators that do not have a built-in reverse lockout lever or switch; if the actuator already has that mechanical feature, a separate solenoid is not needed.

Can the K68-539-00 be used with disc brakes? Yes, disc brake actuators require a reverse lockout device such as the K68-539-00 if they lack a built-in lockout lever or switch.

Will this solenoid work on drum brakes too? Yes, the Dexter K68-539-00 can also be used on trailers equipped with drum brakes.

What voltage is the K68-539-00 solenoid? It is a 12 volt solenoid, matching standard trailer electrical systems.

What are the dimensions and weight of this solenoid? The K68-539-00 measures 7 x 4.75 x 2 inches and weighs 0.58 pounds.

Is there a cross-reference number for the K68-539-00? Yes, the Dexter K68-539-00 cross-references to part number 81103.

How does the solenoid know when the trailer is in reverse? It is wired into the reverse circuit at the brake actuator, so it activates automatically whenever the tow vehicle shifts into reverse.

What finish does the K68-539-00 housing have? The solenoid housing has a painted exterior finish suited to a marine trailer environment.

Is the K68-539-00 sold as a complete kit? The K68-539-00 is the solenoid unit itself, which is installed at the brake actuator as part of the reverse lockout wiring.