2006 pro xs shiter at console wont move

[tritonmerc225xs]

So let's begin, I have a 2006 trition bass boat with a merc 2006 pro xs225. Now I can manually shift the forward reverse and what I think is neutral. This is accomplished by removing the shifter cable and shift manually. Now the problem exists with the control or hand trottle. Now since my boat is riggedbwith a hot foot the only cable connected in this box is the shifting cable. We it seems the control box has locked up, I can push the center choke biting to simply rev the engine with out it being in gear. Still won't crank. So the two major issues maybe be one problem or two. I can have disassemble d the control box to c if something is blocking the throttle moving forward and reverse. A little advice on were to start search would be great and parts or whatever needs to be done