Transmission fault service now message

Sounds just like a faulty transmission control module! One thing in common with all of the ones that fail is that the prnd indicator in the instrument cluster will not highlight the gear selected, like park when you first go to start it. Sometimes they will have a trouble code stored either like in your case.

What can be done about that? Is it something to worry about?

Yes, we should run the codes to see what comes up. this guide will help us:

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

Please run down this guide and report back.

It said 0 codes when I plugged two different code readers in.

The problem may have to become more pronounced before it will set a code. When it does get more pronounced there can be several different symptoms that will arise like a no crank no start, shuts off while driving, excessive battery draw, no communication with scan tool. Let us know if you are able to retrieve any codes from the PCM or TCM.

You may have had a voltage surge when the battery was jumped/battery replaced. lets check the fuses just in case one blew. Here is the guide with the fuse location as well:

https://www.2carpros.com/articles/how-to-check-a-car-fuse

Check out the diagrams (below). Please run this test and get back to us.

It’s actually starting to act like the transmission is going out. But there’s no check engine light.

Are the fuses good?