Till under hood battery is known good, then all other things could be or not be and are speculation. Fix battery first then as I said if codes still exist after X miles or Y starts then get code(s) and if IMA Mr.
@PeterPerkins can maybe assist in narrowing down the issue. We have seen over the years lots of lights random codes and other issues that all went away when the battery was replaced.
Low under hood battery voltage/capacity can cause false errors. Fix what we know is wrong first.
DO NOT RESET anything till battery is replaced. Replacing the battery may reset things, but do not do anything to force a reset of anything till the battery is known good. You want to retain the codes or have them naturally reoccur or reset on their own.
Motor Power Inverter (MPI) Module control the DC/AC conversion (From the Integrated Motor Assisted (IMA) battery's 144 V DC to the IMA motor's 3-phase AC
www.engine-codes.com
It is possible it is failing and caused the under hood battery issue, so once the under hood battery is replaced, keep it on a charger maintainer when parked and have the process for that code followed either by you with
@PeterPerkins help or at the dealer.