Hello! I recently replaced some modules, and the Prius was running great. Then sporadically, I will get a P3000 kicked when I drive it early in the day. Also, it is interesting, in the Dr. Prius app, it will show crazy high resistances for the modules, like 5-10 ohm above what it normally reads, which will return to normal (19) after I reset the battery codes. Also, the prius does seem to be having trouble staying charged, and the battery always seems depleted when I start it, even if I have driven it the previous day and the MPG is down about 10 since I replaced the module. So, I am not sure if anybody has a good way to read the subcodes so that I can get a better handle of what needs replaced, or what this problem could possibly be. My hypothesis is the HV ECU is either sending mixed signals or that there are more modules that need to be replaced. I appreciate any and all feed back that you might have!
It's possible more modules need to be replaced or it's possible your replacement modules are just crap
What JC said. The IR is not 'going back to normal', it is just being reset to a default value until it can work out the true IR.
Did you: clean the bus bars? Torque the bus bar nuts to spec (48 in-lb)? Check the battery ecu connectors for corrosion? Do any testing or cycling of any modules? If all you have done is replace some modules, then you are enjoying that fun filled game called "whack a mole". The chances of having a successful repair are very very small and decrease each time you play. Eventually most give up and replace the entire pack or get rid of the car. P3000 is a code that says, "hey, there's a fault code in the battery ecu". Many here get a mini VCI cable (along with a bootleg copy of Techstream - Toyota's diagnostic software) from amazon or ebay and install it on an old windows laptop. This will let you scan all the ecu's on the car for codes and data- as well as perform special functions (such bleeding the brakes, programming new TPMS sensors, or running bidirectional tests). Posted via the PriusChat mobile app.
It's important to keep in mind that P3000 is not really the code that matters. It is just a code that the HV ECU sets to tell you that there are codes in the Battery ECU that really matter. So besides just looking at voltage and IR readings and such, it's important to start by getting whatever trouble codes are set in the Battery ECU. Those will be the most specific information you've got on what the car is complaining about. Yes, there are also some INF codes to the P3000 in the HV ECU, which will tell you a little bit more than not having them, but still not as much as just finding out what main codes you've got in the Battery ECU.