Im attempting to help a friend fix his washer. I had helped him once before and I remember I found a few simple steps pushing different buttons and I was able to get his washer working again however that was several years ago and I don't recall the exact problem nor the solution ... regardless that's why he has asked me to fix it again.

The issue is the washer will not start... the only button that does anything is the end of cycle/control lock button. if I hold for 3 seconds the light will illuminate indicating that it is in the locked mode and I can do the same and the light indicator will turn off. There is no response from any other of the controls, while locked or unlocked, and Ive attempted pushing several combinations with no luck. however while it's in the locked mode I can still open the door to the unit. I would think the door would lock in the locked mode. does that mean that the door latch is not engaging?

If your duet washer won't start its most likely due to a bad part behind the start button.
Here's how to fix it at home for 35 cents: https://youtu.be/N8rz8sclwAg