Dead inverter or transaxle 276k

First you will need to have the prius properly scanned OR pick up a scanner that reads DTCs and INFs (subcodes potentially related to a DTC), the least expensive option might be a mini-vci cable with the techstream software

That one DTC p0a7a alone has over 10 different INFs (subcodes) that could be associated with it

Without the proper DTCs/INFs it would be difficult to offer any thoughts beyond obtaining such

Question (data reference really), when was the last time the transmission fluid was change (if known).

 

Hey turbo,
Are you saying the stator coils the on MG's both read over 550 Megohms to ground? If so, I think that's too high a reading and may indicate a meter malfunction.

Here's another example of a failed T/A, an '06 picked up from the local dealership that was diagnosed as having bad
tranny, but all codes had been cleared. The vehicle ran ok and all systems working fine, just around the neighborhood
for about a month (I didn't have it licensed for the highway). Finally got a P0aa6 along with subcodes 526 and 613 (indicating a problem with mg2), plus I started feeling extra vibe and hear some extra noise from the inverter. Long story short, tore down transaxle and found a bad mg1 stator coil.

 

Hope you got it reeeeeeal cheap!

GOOD LUCK!