2004 Prius Dead

I have a 2004 Prius with 173,000 miles on it. I went on a 150 mile trip yesterday and it drove fine until it went dead at a light. The red triangle of death came on for 1/2 second and then the dash went blank. When I try to start the car, it shows some lights in the dash and then shows square boxes where the RNDPB letters should display then it goes blank. I can't get any codes from the car. The engine does not start. The windshield wipers move for about 1/2 second but will not continue to their resting point when I try to start the car. The windows will move when I try to start the car if I have a window switch pressed. I tried disconnecting the 12V battery for 1/2 hour with no success. I tried disconnecting the HV battery but still no success. The car's front wheels are locked so the tow truck had to lift the front end for towing. The emergency lights with blink. If I press the start button twice with no brake pressed the multifunction display comes on. I had a maint req light showing with a code for an O2 sensor which I bought and was getting ready to replace.

 

I found an interesting video about the engine control computer. 08’ Prius Engine ECU replacement no reflash (youtube.com) The problem was the O2 sensor code with the engine check light being on. Just like mine. Replacing the ECM fixed the problem. I have not done this but it is a lead. I don't know if the ECM can make the dash display show square boxes instead of the RNDPB letters. However, in pushing the start button with the brake depressed repeatedly the RNDPB letters lighted up correctly twice instead of the square boxes.

 

Yes, It was a blown fuse. #31 "IGN" fuse, ignition system. It's a 15 amp fuse. I replaced it and the dash lit up with the red triangle and the odometer blinking and the fuel gage blinking and all the other lights on or blinking. When I tried to start the car the 15 amp fuse blew again. Any suggestions?

 

I disconnected the inverter coolant pump wires and replaced the IGN fuse. The car dash is back to normal but has the red triangle and all the mait req lights are on. I assume this is because the car sees that there is no coolant pump attached to the system. The car will go forward and back and the engine starts. I know you can't drive the car very far with no inverter coolant. So now it's time to order a pump and fix the problem.

 

Ok, Fuse #31, 15Amp is called AM2 in the fuse box and IGN on the fuse location documentation I have. The only system code present was P0A1D Hybrid Powertrain Control Module. So, I disconnected the 12V battery for 30 minutes and reconnected it. Now there is no red triangle, and the car comes up READY. The only warning I have now is MAINT REQ light. There is no little yellow engine symbol. That was the warning I had about the number 2 downstream O2 sensor I had long before the car died. There are now no system codes - 0 faults found.