Ok, I was digging around and found a third 3400 CD module. I popped it in, and it READS the CD. 
But how is my old module and "new" module both unresponsive? Bad luck? I will do some more switching and seeing if I can get the first two going again. I am happy with at least one working. These macs make me go a little insane sometimes which is why I hoard parts!
**Edit- It seems the problem is somewhere inside where the module connects to the powerbook. I squeezed the whole right side while loading a cd and that is when it works. It seems to have been dropped before I owned it as there is a crack on the rear right corner of the powerbook. For now I will use it for light internet browsing and the space saving device is installed instead to prevent more damage.
But how is my old module and "new" module both unresponsive? Bad luck? I will do some more switching and seeing if I can get the first two going again. I am happy with at least one working. These macs make me go a little insane sometimes which is why I hoard parts!**Edit- It seems the problem is somewhere inside where the module connects to the powerbook. I squeezed the whole right side while loading a cd and that is when it works. It seems to have been dropped before I owned it as there is a crack on the rear right corner of the powerbook. For now I will use it for light internet browsing and the space saving device is installed instead to prevent more damage.