2013 PCX 150 no start and flashing fuel gauge (all bars flashing)

[bob2013PCX150]

I have a 2013 PCX15-with about 4500 miles on it. I brought it out of storage, and it does not start. It has full fuel bars flashing continuously no matter what the level of fuel. I filled the nearly empty tank with non-ethanol gas and a bit of Mechanix in a Bottle. I also cleaned the battery contacts and put in a fully charged, BRAND NEW, NOCO lithium battery with 14AH capacity, but the scooter doesn’t start and just cranks over briefly (doesn't spin continuously, but only cranks for a few seconds with the start button. This can be repeated almost continuously, and occasionally it will crank longer). It has ignition, as it will kick over with a spray of starting fluid. Does anyone know the cause of the flashing fuel gauge? Is that flashing independent of the bike not starting (i.e. stuck fuel float that doesn't affect bike's ability to run)? Any troubleshooting tips? It seems a lot like a tip-over switch sensor that cuts off the fuel supply, since there is no check engine light (not sure if it would throw a fault in any event where the bike is not actually running, though it ran for ten-seconds on ether.). I'm also wondering about a possible corroded ground which would cause a high resistance and might cause a lower voltage across the components. The bike ran fine the last time I tried it. Any tips on tip over switch, injector cleaning/troubleshooting, or fuel pump troubleshooting would be appreciated- particularly if known to be related to the flashing fuel gauge, Thanks in advance for any solutions or suggestion, I am stumped. Also, I would appreciate any wiring diagrams or troubleshooting matrix. Regards, Bob