Hmmmm that power transformer was not in the box. I will have to search for that then

Hey everybody, newbie here.

For Christmas this year I decided to setup our royal blue train as it's a lot more animal and child friendly than any of my O-Guage stuff. It's the G-Scale model powered by 9V batteries. I haven't used it for at least a few years but last I remember it was working great. Now when I flip the switch for it to turn on nothing is happening. I tried putting a new 9V battery into the coal car and checking the plug connection and it seems fine.

Does anybody have any suggestions on where to go from here?