Loose tender wire

Well, the right way is to use a crimp tool and the proper Hirose connector pin.  If you're careful, removing the pin and stuffing the wire in and a spot of solder.  That's sometimes more difficult than it sounds as the pin may not fit back in the connector unless you're good with the soldering iron.

You'll also have to take the little screws out of the drawbar attachment to free the connector to work on it.

gunrunnerjohn - thanks for the assistance.  After removing the screws from the drawbar attachment, I was able to solder the wire back into the plug.  The soldering was a bit tricky, but I was able to get the solder to hold the wire and pin together.  The engine now starts up and runs successfully.  The only thing I can't get to work is the backup light on the tender.  I'm not sure if I have a DCS setting wrong, or a different wire is loose in the tender. 

Hard to say what is happening with the backup light, I suspect another physical inspection is called for.  Since the board that controls it is in the tender, it's a flaw in the tender I suspect.