Problem with charging my plug-in hybrid via Sungold 4000w inverter

[mpickus]

I have a Sungold 12v 4000w Pure Sinewave inverter set up and connected to a 12V-560Ah LiFePO4 battery bank that is fully charged to 14.6v. AC 110V output works when I test it with a 1000W hair dryer but the inverter beeps once (red alarm LED turns on briefly) and shuts off when I attempt to charge my plug-in hybrid Kia Nero. Note that the other LED error indicators (Overload Trip, Over Temperature Trip) do NOT light up. I checked the car charger with a clamp meter and it draws 3-4 amps at 110v which the inverter should easily handle. I have reached out to Sungold tech support but haven't heard back yet. Any suggestions would be greatly apppreciated!