Could Eren control the founding titan power?

Manga Spoiler: Control of Rod Reiss

A very short answer is because Eren doesn't know how.

Spoiler below:

Eren has what one "The Coordinate" that was given to him by Freida Reiss through his father. This is the founding Titan's ability that enabled them to control the Titans and manipulate their memory.
We don't yet know exactly how this force works. The real limit of this power is unknown, but it can be seen to go so far that Titans carry out acts that threaten their own lives. Rod Reiss also mentioned that the force is so strong that it has the potential to wipe out all Titans if the user can use it to its fullest.

Then why it was that Eren couldn't use it while in contact with a royal bloodline is why Eren only had that power has shown in very rare and unique circumstances . One can argue that the danger to his life was such a circumstance, but unless the writer dwarfs the exact nature of that power, we do not know the limits.

More information about HEAVY SPOILERS can be found at: Wikia: Founding Titan

Ryota

Many Thanks! The detail and consistency of your answer is just great.