there are 2 plugs on it the 4 pin one is for the pcm and the other one is for the indicator lights and for the park neutral when i did my harness only the 4 pin one stayed the other one i took out so on my truck all i have to do is plug in the bigger of the 2 and that will run the indicator lights. whether the psi harnes includes the 4 pin plug i have no idea but its the bigger or the 2 that controls it so dont cut that one off