Another manual control is the throttle valve. This is a valve that's connected to the throttle so that the transmission knows how far you are into the throttle. The valve is connected to the throttle via a cable. The cable is often adjustable.
If it gets out of adjustment, it can cause shifting problems. Honestly, it's not likely to come out of adjustment unless someone puts it out of adjustment, say if you've recently done work on the intake manifold or throttle body and you had to disconnect the cable. My point is, don't start adjusting this cable unless you have reason to. It's not likely to be out of adjustment, but if it is, it can cause a shifting problem. I don't have a video on adjusting a transmission throttle cable, but you can use the info in this video as a starting point.