Replaced 2 Transaxles and the HV Battery and Still Not Working... advice please.

A used trans should just work.

That message implies an electrical problem. It is very common when the 12V battery is insufficient to completely power up or power down the car. So tell us the terminal voltage of your 12V.

Next would be to check fuses and relays related to the parking pawl motor and the transmission ECU.

Next would be to swap parking pawls with one of the other transmissions.

 

wow. :welcome: to priuschat, all the best!

 

If left installed in the car, the 12V will die within 2-4 weeks of non-use. If left dead for more than a few days, it will sulfate and not hold a charge. It is very important that you have a known-good battery installed while you work through the other issues, because all diagnostic codes, including those for the hybrid battery, are red herrings if the 12V is no good.

 

i had the same issues and i had to replace my inverter converter and also my trans. after that the car was perfect. not sure if that would help youout but i had the same screen as you telling me to put the car in park.

 

I would change the battery if it is reading 11.8V. Mine is always 12.4 + . If it drops below 12v its history. Charge it and see if it will help your situation. Hal

 

since you already changed the 12v, is it possible the charging system is not working properly?

 

That's what you get with the car turned off? That battery is almost dead. Put another 12V in parallel with it and try to start the car.

 

I had the same screen message on mine for nearly a year until last Wednesday when I replaced 12V aux battery. I am in Europe so i could go for cheaper VARTA battery, I heard that users in US using OPTIMA YELLOW TOP battery and since couple of months there is a direct replacement to prius 12V aux battery with slim Japanese terminals (L+). Since I replaced my battery I don't have any more this message on the screen which you showed.
The way to start my prius while the message (your message on screen) was displayed was to press+hold the brake pedal and during the same time power off the car, then without releasing your foot from the brake pedal press once shortly the power button, keep your foot on the brake pedal and let the capacitors to charge braking system.Next press the power button one more time if car didn't go to ''ready'' mode, this time it should. - this procedure always worked.
However since you have all suspension and other elements ''loose'', you may need to ensure your hydraulics (brake hoses) were not exposed to allow any foreign air into the system. Hence if you allowed the air then you need Toyota scanner (main dealer) to release correctly the air from your brakes system (not possible to do it DIY).
It's possible to replace the brake pads without opening the bleeder screws -- see here. This still requires some extra steps (like removing the ABS relays).
From the picture looks like you may have had low brake fluid or your car is lifted high at and angle so fluid moved in the reservoir. If you didn't touch hydraulics make sure you do not touch them. If any of your brake calipers are ''open'' make sure do not install 12V battery at this stage as your prius will sense that you are trying to set car in Ready mode and will create pressure in the system which will shoot pistons.

Since you only posted yesterday, give more advanced members some time to response, perhaps during weekend as some may not returned home yet from long holidays. I'm pretty sure you will find out what the problem is and it will turn to be relatively small problem as it's Toyota.
Don't panic as you probably didn't re-connect something correctly. the picture with 3 trans-axles looks cool! Don't buy any more - at least 1,2 if not 3 are still good.

Lastly, I heard people buy some professional scanners which read hybrid specifics codes (i'm sure someone here knows which scanner you need). The when car is fixed people re-sell scanner for still high price.
:welcome:

 

Please take some good pics. I plan to do this when my car hits 300k (100k to go). And yes, you have an electrical problem. These CVT transmissions are bullet proof. Just read the 200k/300k threads. Good luck and please report your findings.

 

I agree with your decision to do #2 above.

When you contact the tech, ask what his diagnosis is and the DTC logged by the car. If you provide both then we can comment on the likelihood that some other issue (besides the diagnosed problem) might exist. Good luck.

 

You need >10.5V at the parking pawl to make it work. If the car is not in Ready and the 12V is too weak, then it won't work. Other than that, check all electrical connections, at the pawl and the Trans ECU, and perhaps swap out pawls. You've got like three of them to choose from?