15 Nali

Help Needed,,,, hello all , I purchased a set of the Tri-mode steps for my 2015 Sierra Denali and followed Phil’s diagram and made my harness but I cannot get them to work correctly. Thinking I maybe Have done something wrong I made a new harness checked it over and over and I bought a new module and to my surprise it continued to do the same thing. When I enable them and open a door they slide all the way to the back. Today I had tech connect his computer thinking it might need to get flashed or programmed and after 4 hours he could not get them to work. I’m at the point where if I can’t get them to work they are coming off. I would really appreciate any ideas. Thanks in advance.