P1784 P0700 and P0731?

The P0700 code is just telling you that you have other transmission codes as some code readers don't pull codes from other modules, so it is there to tell you to look for the other ones.

The P0731 is a gear ratio error in first gear.

The P1784 is a solenoid code that would need to be addressed. However, I would suggest going through the P0731 as that will most likely lead you to the issue of all of the codes.

Please run through the attached info and let me know what you find and what questions you have.

Thanks