Repair isn't practical, and a new one is a lot of money. Assuming yours is a 2004 or later model the best price is around $150 at a wrecking yard. Some want a lot more but you don't have to buy there.
EDIT - be sure to pull the disconnect plug at the hybrid battery before replacing the inverter, and purge the inverter cooling loop when you start the system.
Inverter failure is quite rare but is not unknown. I am not aware of any failures that brought in inverter codes and were not the inverter. However failure of the inverter cooling pump is much more common and you need to be sure the codes are not for that.
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