Battery/inverter

Clean the battery terminals. Then test the batteries.

Converter.

after the clean, check voltage at the battery from the battery terminal and post back.

Hmm, since we have no clue as to what the problem may be, we may have to resort to the "Process of elimination." Did you inspect the circuit breakers and fuses first?
I carry a fues kit, you can get them at WAl-mart, there are like 10 different fuses in the pack. Just throw it in your "Maintenance" storage compartment, it's good to have.

Please start by telling us what troubleshooting you have done.

Our Wild A** guesses could lead you all over the place-- not reasonable for you and could be very misleading for the next person to experience this.

If you need a step by step for troubleshooting, let us know.

Start with the basics. Have all your batteries tested (it's free) - inspect tighten battery terminals - check grounds.

Ford chassis?
Try cycling your battery disconnect switch.

I would guess low battery voltage. Put a meter on the battery terminals to verify.

The question is then why is the battery voltage low?

Engine start, and usually dash radio and generator operate off the chassis battery. Dirty terminals or loose connections can cause the intermittent problems.
On my CRV I had a problem where I would shut the engine off, and then try to restart 5 minutes later and NOTHING, No start, No lights or anything, I got out and wiggled the positive terminal connection and voila, everything OK. The terminal was cleaned and tightened as much as possible but it was still not tight enough, I had to put a shim in it and no problems since, the battery terminal appears have been made too small.

Ken

Well, I guess he got it fixed or gave up. He never came back with an update. Glad to be of service. lol