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refurbished hybrid battery still not fixed codes p0031,p3190,p2237,p0304,p0031

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by nickster78, Jun 16, 2022.

  1. nickster78

    nickster78 New Member

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    Hello, I have just reconditioned my 2008 toyota prius hybrid battery with a cq3 battery charger doing 4 cells at a time and reached all 28 with a full charging of numbers at low number of 5100mah minimum and the high number at 7500 mah. connected all the cells and let sit like 30 hours...I did a voltage reading on all cells and they all matched at 8.05 volts...I put the battery back in and tried the car... turning on the screen showed 5 bars of blue on hybrid battery. I drove it and eventually the bars went down to zero, and the red triangle came up. I checked the codes and got and p0031,p3190, pending are p0304 cylinder 4 misfire, p0031, h02s heater control circuit low, p2237 o2sensor positive current circuit open. Tried the dr prius app and auxillary battery was at 14.0 volts, the battery pack voltage showed 225.18 volts, state of charge is 58%...sitting not running it went to 230.80 volts. I am wondering if my main ecu is faulty on this car? I replaced the hybrid ecu with a used one and that didnt change anything...I assume my hybrid battery is ok? I see some people had trouble with the main ecu on you tube...
    Thanks for any reply

    Nick
     
  2. dolj

    dolj Senior Member

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    It sounds like you think the ECUs are lying to you. Have tried to troubleshoot the cause of the O2 sensors fault, the misfires, and poor engine performance?

    None of those codes indicate a hybrid vehicle battery problem. However, a poor-performing engine can cause problems for the HV battery eventually if not dealt with.
     
  3. Tombukt2

    Tombukt2 Senior Member

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    Sounds like the dreaded 2Z head gasket failure when you go to fixing that make sure you look carefully at your pistons in the bores it seems in these engines he's open deck z engines they have some problems with the Pistons Don't know exactly what Don't care I just know the rod can break easily and you may not even know it you'll be running on three cylinders and the thing will be bouncing around like crazy and boy disastrous and if you're going to fix that you're going to have more money in that high mileage thing you got then you will by getting a JDM spec engine out of Japan just the way it seems to be JDM has warehouses coast to coast I bought the engine and the transmission so that what I put back in the car has similar mileage around 65 70,000 versus my 215 k
     
  4. mr_guy_mann

    mr_guy_mann Senior Member

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    Maybe the engine ecu (ECM) is telling the truth and there is some problem with the Air Fuel sensor or its wiring, which could cause misfire, & poor engine power- and that could result in poor charging of the HV battery. None of those codes have anything to do with the hybrid control ecu.

    Posted via the PriusChat mobile app.
     
  5. nickster78

    nickster78 New Member

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    Vehicle:
    2008 Prius
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    Two
    I just replaced the o2 sensor and it didn't change a thing! I got it running and 5 bars of blue on the screen were showing then drove it, and the bar went down to none, I checked the codes and they came out as p3193, p0003, then changed to p0302, then p2237, then p0031.
    Checked battery voltage on dr prius app and showing 222.85 volts and 59.22% state of charge. It will run good after taking off ground cable for a few minutes, hook back uo shows 3/4 bars of blue, then bars on screen drop down eventually to no bars the the car runs funny, slow also. only 3 blocks from home. I saw a guy replacing the front cpu under the glove box and he said there were stuck codes he couldnt get out and changed this front cpu or cpm and now its fine?

    Nick