Help ICE wont start, Comm buss Down after Cat stolen/replaced

My 2005 prius had the Cat stolen. Drove it 20 miles to repair shop ok....but did not have it repaired after got estimate. Then 2 miles home and entire Gas gauge bar was flashing on and off all the way home. Parked it outside. Later drove it into garage and entire gas bar was still flashing, AND red triangle was now on, along with abs, vsc, traction, brake lights. I assumed it was just cus the O2 sensor and cat were gone. I jacked up one side, replaced the O2 and cat. Took it down, and all the above lights were still on. Took it down the road 1/4 mile, realized ICE engine was not coming on, turned around, and ran out of power. Synergy drive had now disengaged. All above lights on and red turtle energy monitor light on in lower display. 12 volt battery was also going dead, as it had mostly discharged while I was working on car with hatch open earlier. Had to jump 12 volt to get car to go into neutral and then pulled it 1000 feet home.
Charged 12 volt up, put 5 gal of gas in the car after reading it takes 3 gal if you run out before car will start ICE motor, for it was low on gas all this time as one bar was flashing before any trouble started and cat was stolen. CAR will STILL not start ICE. Used Torque . IT says no communication with ECU, Buss is down. Fault Code "U0100 Data bus ECM no communication" No other fault codes. I then used Dr. prius, IT says battery is at 24% 212 volts, 7.59 cell voltage, .05 voltage differences. No communication with ECU... Error codes are POAA4, CC100, CEOAA, P1300.
I have used Torque app and Dr Prius to reset codes, and disconnected 12 volt battery, and orange drive battery cut off switch, for 30 min after resting codes. NO change. Same codes, same messages about no communication, ICE will still not start. All the above lights are on and entire fuel gauge bar is still flashing. I have no idea why red triangle came on in first place, but had at first thought it was because of no cat or O2 sensor. I speculate that Maybe during the repairs, jacking up one side of car pretty high, with the tilt, it felt it was out of gas and that is why ICE did not start after the cat repair? I have no idea. Please help. I have no idea were to go from here. ??? PS. Just did Torque again to get a screenshot and now it also shows POAA4 powertrain code, along with U0100 from before . Here is short video of how it all looks when I turn the car on.

And am attaching screen shot of Dr. Prius. and Torque display.

Please help, what can I try next? THANK YOU

 

Well I sure hope not, I would not have thought that could happen, good to know for the future. Do you think if it had, that the car would have kept running? I guess more important any ideas on how I could check if the ECU is ok? Further I guess a replacement salvage ECU would have to be programmed by the dealer before installation too? Thank you for the idea...though I hope this did not happen. hope it will prove to be something else....

 

THank you much! to all who have replied! I ordered the VCI cable and techstream as you suggested....so I will be able to do more detailed testing. I found no bad fuses, all seem to be OK. I also found that in torque in settings it claims it is indeed not communicating with ECU. I found a place that said to check the communication circuit by using a DVOM to read resistance between diagnostic port connection terminals 6 and 14, and if it is 60 ohms that is good. I did this and it is 60 ohms. I am adding images about this now.

I wonder if anyone has any comment on the other code that is coming back POAA4 "Hybrid Battery contractor circuit stuck closed" I have the drive battery open already, is there a place I could meter to see if this relay is really stuck open or if it is a communication issue giving this code? IF so can someone advise me were to meter and what to look for?

I also got some sort of a PDF manual, but it is too complex for me to identify just what connections to meter to see if ECU is getting ground and power. Nothing happened to the car that should have created such a physical issue. If there is anyone who knows what wires to meter and what to look for, I think I can find the wires and test this?

Sounds like to me the consensus, as I understand it, is that perhaps I could buy a used ECM and try it. IS that a correct assessment of a good thing to try??? And if I do, and plug it is while leaving the old one in, do I need to ground it?? OR do the connectors take care of that?

Thank all for assistance again...

 

Thank you, I am not driving it, could not if I wanted to. By fried, I think you mean, ECU is toasted. I am planning on trying a new one. Do you know if I have to do something to get a new ECU to recognize my keys?

 

Thank you very much. THis post is helpful! Helps me know what is important and direction I need to take next. I am going to get a replacement ECM and try it...seems like the next step while I wait for my techstream stuff to arrive. Do you know if, a new ECM will require me to reprogram my keys, or if they will still work?

 

Yea. I recieved my tech stream and got it installed and working. I hooked up to the car and tried to access the Engine ecu. It said "selected system is not responding or is not available Please check the repair manual for applicable systems" So I checked the HV battery system live for codes and it said "code U0100 lost communication with the ECM/PCM "A" " SO is there anything else to do, or to check now that I have the techstream up and working, (per above suggestions to get TS for deeper diagnosis someplace above) or is it time to replace the ECU? Also is there a good place to learn about how to better use this TS tool...pretty cool! and as always...thank you!

 

Thank you, I would love to do this, but I do not see that option. I am attatching a picture file of what I see on my main techstreem screen. I can not find health check in the menus or on screen, can you guide me as to how to get to this choice please?

 

OK thank you much, as well as the poster below. I checked other modals and they are working. I would love to check the ground and power voltage to the ECU if anyone can tell me which pins on which connector and what voltages to look for I would appreciate that guidance.

 

Well I went ahead and got another ECU and put it in. The car acts excatly as before... Red triangle, yellow lights, red turtle, etc...says "problom" for a moment on power up, will not engage into nutral, or drive or reverse, or start engine. Dr Prius and torque both say codes PoAA4 and U0100 power bus issue...no ECU communication. ANY IDEAS on what to try next??? Measure the power and ground wires to ECU?? IF so does anyone know what wires and what voltages to look for?? Other ideas?? Reminder that above I checked this circit resistance and it was good...and this was suggested...."Well, the resistance test on the CAN bus is good. Since there are two terminating resistors (one 120 ohm in the ECM and one 120 ohm in the battery ecu- in parallel = 60 ohm) it means that the network wiring is intact - to the ECM. No comm fault is gotta be missing power , ground, or damaged ECM. Will see if I can go over diagrams later." Can anyone help me with checking the power and ground lines??? or other ideas?? I can not imagine what happened to cause this problem to happen. THank you to all in advance!!