2005 Prius - after ECU replacement, car won't turn off... electrical problems

Great point - this is a link to an unlisted youtube video of what happens when I connect my car battery:
https://youtube.com/shorts/ujdo9ufyxuU?feature=share

 

I did not program the key fob to the new ECM, but I have since been able to put the car in drive twice.

 

I have not put the old ECM back in yet - does that seem like the most logical next step to you?

 

Hi all - since your replies I have not been able to recreate the issue to test out these suggestions. Each time the car has turned on and off normally with the key in my pocket. So it works but doesn't seem reliable enough to actually drive anywhere.

 

Hi everyone - I wanted to update this thread to mainly say that since I replaced my combination meter, I have had no issues with my car! So anyone having the same symptoms as me, good chance it is your combination meter even though Texas Hybrids didn't think so. I wanted to wait until the weather got cold again to be sure, so that is why I have waited so long to update.

The main source of the diagnosis confusion (besides my dash lights not going dark) seems to be that I was getting some codes from the ODB scanner that were for something else, namely my ABS ECU. I actually reset those codes and they haven't come back. Nice.

When I decided to go for the combination meter replacement, Texas Hybrids had increased their costs significantly, so I ended up ordering from Module Repair Pro in CA. There I specified that I have a 2005 Prius, and I ordered a cluster exchange that claimed it would fix the bug where the odo won't count above 299,999: 04-05 TOYOTA INSTRUMENT CLUSTER DISPLAY EXCHANGE - Module Repair Pro INC I now don't believe that Module Repair Pro can actually fix that bug in a 2005 Prius (They have not updated their website since I pointed that out, so maybe I'm the dummy here, but be warned)

Only after a full dashboard disassembly, replacing the combination meter, and then putting it back together again did I realize that they had sent me a 2006 Prius combination meter (should fix the 300k problem) but without the "required parts to make it work properly in your 2004 or 2005 model vehicle" that is advertised by Texas Hybrid Batteries: Rebuilt Combination Meter 2004-2005 Prius w/ 300K Mile Upgrade | texas-hybrid-battery

The consequences are that even though the fuel gauge, odometer, PNDR gear display, and left turn indicator lights all worked as expected, seemingly every other dash light was mapped incorrectly. For example, when I turned on my headlights, instead of the headlight symbol lighting up on the dash, the symbol for the rear defrosters came on. When I turned on the right turn indicator light, the headlight symbol flashed, etc. A simultaneously hilarious and discouraging problem. Texas Hybrid Batteries must know how to make an adapter. They are also the only place I've seen that advertises being able to program your desired odo reading into the new combination meter. A shop I visited in person said they would only repair rather than exchange so that the odo reading wouldn't change, and Module Repair Pro will just send you the one with the closest mileage to yours (but for me, that was still 6k off). After the shenanigans -- and at first Module Repair Pro did not believe that they had sent me a 2006 combination meter, I had to call them on the phone and send pictures -- they repaired my original module that I had sent them, I returned the 2006 module, and after the third (and final) dash disassembly and reassembly I put in my fixed combination meter with my car's real mileage and I have had no trouble since. Yay!

Thanks everyone for giving me the confidence to fix this myself!