The trailer brakes get stuck everytime I come to a stop

Hello and thanks for taking the time to help me

Every time I come to a complete stop(with a trailer), it’s very hard to start moving as if the trailer brakes are set.
This doesn’t happen bobtail and it DOES happen on multiple trailers.
Once I aggressively force the trailer to start moving everything seems fine. I can drive on the highway and everything seems ok until I come to a complete stop.
Once stopped its very difficult to move the trailer either forward or backward as if the brakes are set again.

I did find a work around:
When I remove the BLUE glad hand to the trailer, I can easily move the trailer.

I don’t have a manual trailer brake lever in my truck so this leads me to believe that this may be related to this TRAILER HOLD switch I do have(which I made sure was OFF). If I’m not mistaken the TRAILER HOLD switch sends air through the blue line to apply the service brakes on the trailer? If that’s faulty what would I need to replace?

Any ideas would be greatly appreciated

I have a 2016 Freightliner Cascadia sleeper with a DD15 engine and DT12 transmission.

 

do you think that quick release valve also applies to trailer brakes? My tractor brakes are perfectly fine even when my trailer is struggling to move I can tell my tractor is able to move freely.
Also even if I let go of the brake pedal and wait an entire minute my trailer is still unable to move, unless I aggressively force it to. I thought the purpose of the quick release valve was to quickly release the air from the brake chambers on my tractor after depressing the brake pedal?

Thanks for the response

 

Ahhh I see. I always wondered what that thing did. Mine looks a little different(see pic) but it’s definitely the quick release valve to the blue line. I will buy this ASAP and keep you posted. Thank you so very much!

 

YOU GUYS WERE RIGHT! Thank you guys very much unfortunately I couldn’t remove the #### thing myself it was so corroded it felt like it was welded to the fitting. Had to have it sawed off. Now I’m going to replace the quick release valve under my 5th wheel for good measure. Thanks again you guys are great!