Ford V10 not charging

Measure the voltage across the chassis battery with a $10 volt meter from an auto parts store. It should be just over 12V with the motor turned off, and over 13V with the motor running.

It could be that your battery isolator is switched over to the coach batteries. Take the same measurements at those batteries. If they are getting charged, you might be fine because your new chassis battery may be fully charged and so the isolator switched the alternator to the house batteries.

You just might be okay.

You showing a warning light on the dash? Put voltmeter on starting battery and confirm the no charge.

Other than checking wiring I'd suspect the alternator or wiring issue. I'd certainly go over the wiring out of the alternator.

You do have an emergency backup in the form of the coach generator (or solar). As long as you have a relay type house battery isolator, once you start the Ford engine the house system will backfeed into the Ford's electrical system.

Since you have started the vehicle take a close look with a flashlight and find the wire you dropped. Happens frequently. If no wire has been dropped perhaps the alternator is bad?? Is this why you changed the battery because it was dead? If possible you may be able to jump your batteries together and let the generator keep up with the charge until after your trip. You may be able to prop the emergency start/ aux start button versus running a jumper cable.

If you think the alternator is faulty, just make sure the charge voltage is not stuck going to the house battery(s) in back. The isolator/solenoid could be stuck supplying power in back instead of prioritizing of front/chassis battery first, house/back battery afterward.

Why did you replace the battery? How long has the alt been bad?