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Q: My problem now is that I have a code P1636 HV ECU malfunction on 2001 Toyota Prius

Just about 4 months ago I got a stupid idea that I wanted to learn about the Toyota Prius. I couldn't find any classes locally at any of the colleges.
I bought two 2001 priuses to serve as my text books so too speak, both had bad HV Bats, I got lucky on the first one, it had been rebuilt within the lat 2 years an had all 2nd Gen Modules.
I replaced 1 module at the cost of $40 and that one runs great. The second one had set for a year or two and I had to replace all 38 modules out of 2 07 bats. Both batteries perform very well. the second prius had a secondary problem. I could charge my HV Battery up to the highest level that the prius would charge it. I would then reinstall it in this problem prius. I would start the problem Prius and enter the Ready mode, the Energy flow screen would show energy flow from the ICE to the electric motor an then to the HV Battery, which looked completely normal. The problem was that the HV Bat was being drained rather than charging up.
I put a analog volt meter on the HV Bat put it in the 500 V range, in the Ready mode the Bat was being pulled down from 300 V to 240 Volts an after a few minutes the devils triangle would come on an it would tell me I had a HV Bat problem. Stupid car didn't have sense enough to know it was never a HV Bat problem. I just replaced the complete transmission along with MG1 an MG2. I had megged out the MG1 an MG2 stators to chassis or ground an got near an infinite reading. I didn't bother with milliohm meter reading since the 3 winds are in parallel and me not being sure if I would need to measure AC impedance or just DC ohms for the test. I figured the resistance would be so low as probably not a good reliable test.
I bought a transmission for $400 and replaced both MG1 & MG2.This solved my first problem. After replacing the transmission an trying to start it I couldn't get it to run. I learned real fast what just one bad igniter will do. After replacing one igniter I now maintain 300V in the ready mode and the car runs out pretty good.
My problem now is that I have a code P1636 HV ECU malfunction. I assume it is the ECU under the passenger side around the glove box and not the HV Battery ECU.
Am I thinking right??????? Also if I swap out the HV ECU do I have to jump between pins 4 an 13 of the DLC for 30 min with ignition on to set up the hand shake with the immobilizer ECU????
I think before I do much more I will put it the rest of the way together. Right now I just have 4 bolts holding the HV Bat in position an still need to put the cover on it an hook up the cooling fan an vents etc for HV Bat. I was also getting the code P3077, Yea , I guess I could have a problem with my HV cooling fan since it's not connected or hooked up'
I suppose I am a little doubtful that the P1636 for HV ECU malfunction will go away after I got everything hooked up.
Have any helpful ideas for me????
Thanks, Hank
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