Need help with a weird lighting issue

I have an 07 International 9400i. I recently changed all the main lights (headlights & turn signals) to LED's. The headlights and turn signals work just fine on the truck itself, however, the trailer turn signals don't actually flash but simply stay on. I have a CEC electronic flasher, model EF32, 25A, which is supposedly compatible with both regular and LED lights. 20A fuse on the truck flasher/turn signal, and 2 15A fuses for trailer left and right turn signals. The strange thing is that even though the turn signals actually work properly on my truck, the dash turn signal indicators also stay on solid like the trailer lights.

This looks like the flasher relay that I have, except mine doesn't have the ground wire on top: https://www.amazon.com/CEC-Industries-EF32RL-Flasher/dp/B00JXLH7CG

 

But then why does my dash indicators stay on as well? Also wouldn't a short affect regular lights as well? I did not have this issue with regular bulbs.

 

I don't currently have a trailer, I pull Amazon loads. But as I know, their trailers have a regular bulb on the side turn signals, and LED's in the back. Both had the same problem of simply staying lit up after I turn on the turn signal. I guess I can check using a multimeter on the electrical trailer line...? Could a bad ground on the relay cause this?

As far as the LED's themselves, they are not marked with ground and power, seems to be reversible. I'm using Yorkim 3157 LED bulbs, if that helps.