TDM 24CX-4 Stereo 3-way / Quad 2-way questions

To be more specific..... My TDM comes with 4 inputs for quad 4-way operation.  The manual says there is a channel link switch on the back to link channels together and make 2 stereo 3 way channels.   There aren't any exterior channel link switches.    There isn't an on/off switch as well.   I've found a few other units online that appear to be the same as mine.   Any help would be appreciated.

What do you want to achieve?

My guess is that you or someone competent to do it is going to have to open the chassis, take a look at the internal wiring, and then modify the connections to suit your desires.  You have not really said what it is you desire, but I am guessing you want it to operate as a 3-way in stereo.  When you say "quad 4-way", a reader might take that to mean there are 16 filters that comprise 4 channels each of which provides for 4-way operation of a single speaker.