2008 Prius Dead No Radio, MFD but headlights work

Perhaps the start button has a bad connection or is broken. But first check the 12V battery voltage.

 

First question is 'was the original AM2 fuse open?'
If the original AM2 fuse was open, did you correct the problem that caused it to open, prior to installing the spare?
If the fault was still present, then the new AM2 fuse is very likely open now, also.

The AM2 typically burns open due to the inverter cooling water pump failing. You can unplug this pump from the circuit at two places. One is at the pump itself. The second location is easier to access and it the one wire connector just above and to the passenger side of the underhood fuse box. If you suspect the ICWP to have failed, disconnect that plug first, before replacing the fuse.

 

... and if I were facing such an issue and it turned out not to be the AM2 fuse, the next thing I would probably do would be to fetch the wiring diagram (more info) and my multimeter, and just start working down the likely paths in the diagram checking where power is and isn't. There are a few basic routines in diagnostics that kind of have to be done up close, though faraway people on the internet can sometimes help with questions that come up from what you find.

 

Have exactly same problem

 

Same approach to diagnosis ought to work

 

Obd has a live but cant cpmmunicate with any module