Ranger Trailer Reverse Solenoid?

I posted this in the Ranger section but wanted to try my luck here as well:

Looking for some information.

I have a 2006 521 with dual axel trailer (disc brake on the rear axel) and Tie Down Engineering 70lp actuator. I called Ranger and actually got a brand new "complete" actuator. What I didn't notice was a reverse solinoid? My old one doesn't have one either (I am not the original owner of the boat and don't assume everything is "right").

Is this right? How does the trailer reverse without the brakes engaging? I haven't had any issues to date and whole I have everything off I just want to double check this is correct.

Thanks for the help!