Ok, So I was driving for a couple of hours today in my recently acquired 2001 Prius, when the red warning triangle and the check engine lights came on. The car seemed to still drive fine (70 ish mph cruising). Got home after about another 30 mins driving, plugged in my Chinese VCI cable, and read the codes P3000 and P3020. The traction battery was replaced in this car by the Toyota dealer in 2013, so how likely is it that block 10 is bad? I was thinking about pulling the battery and cycling the modules in block 10 with my hobby charger. What else should I look for, corroded sense wires? Burned multi plug? I have attached an image of the freeze frame of the error code, and to my untrained eye, block 10 seems ok. I reset the codes and ran a few errands with the car and all seemed fine. Any advice would be appreciated.
Hi S Keith, The screenshot was the freeze of data associated with the fault code, that was all of the data captured. I'll do as you say though and cut back the data fields to the ones you suggest and record the forced charge, but this will have to be tomorrow now. Its dark and the neighbours won't appreciate it I can tell you that the IR of the blocks 3 and 10 are the highest at 0.025, the rest are between 0.022 and 0.024 ohm. Thanks for the help, Ben
I can't tell you if the car sat unused. I do know that it has done approx 18,000 miles since the battery was replaced in 2013, according to the service records. I have also been in contact with Toyota about the battery only being a couple of years old and already failing, and they didn't immediately dismiss it. I had a message back saying that they will look into it and get back to me. I tried to upload a .ZIP file with the exported data, but that didn't seem to work, so I've uploaded the CSV straight to my google drive. Hopefully everything that is needed is there. I'm new to this software, so taking some time to learn where all the functions are. PRIUS_1FX_12-12-2011 230402.CSV - Google Drive Thanks
Hi Steve, Thanks for having a look at the results for me, it's much appreciated to get an experts opinion on the matter. I did try to do a discharge test, but unfortunately I could only do a stationary one, but did coax about 10 amps out of the battery. I will try to do another one when I find an open space to try to get more load by slipping the brakes as you suggest. The results are uploaded in the same format onto my google drive. PRIUS_1FX_14-02-2016.CSV - Google Drive I'm not sure how valid they will be, I did struggle to regulate the load at the beginning, but they do show that the block 10 is the lowest voltage block through the test. So if I have no luck with Toyota, (which i'm not getting any hopes up about anyway), The grid charging should even things out? I read the thread in your signature to try to understand a bit more. I would need to charge the pack with a constant current upto 100% SOC, then discharge them to a certain level? I think we have a 'spare' HV regulated DC output PSU at work that may do the trick. I think it has adjustable voltage and current limit. What voltage and current limits do you suggest for charging? Thanks, Ben
Steve, Thanks for explaining that to me and for spending time analysing the data. I'll wait to see what Toyota have to say to me this week with regards to the battery. If they don't play ball, then i'll have a go at the grid charging and the discharge test to see if the result of the delta V is any better. I'll have to hope that the HV PSU I mentioned about hasn't been disposed of from work, otherwise i'll have to become creative. I'll keep the thread updated. Ben.
Not sure that you can get any serious improvement with a grid charge, particularly since one or more modules have indicated signs of failure. You may better start with module level work.
In terms of replacing the module in that block or cycling that individual module with my hobby charger?
I just had a customer come in with a pack that was well balanced, but it had terrible capacity. 260,0000 miles with original battery pack. Car constantly swung through the full/empty on Battery pack screen. But it never made the car code since it was in balance. Interesting to see.
Well when I was taking the battery apart this weekend to connect the grid charge cables, look at the corrosion I found. I think that this may have been the cause of the 'bad' block 10. I cleaned up all of the copper link bars, cleaned up the backs of all of the nuts and all of the cable terminals and reassembled the battery. I did a forced discharge/charge this evening and not one time was block 10 a minimum voltage or maximum voltage block. In fact the voltages in that block were just about average. I still would like to do the grid charge to try to balance things out, but that'll have to wait now until next weekend. I have the PSU here at home now too, so no excuses. It's an old 'Glassman' that does upto 1.5Kv @ 500ma max.
I doubt the corrosion was the issue. I've seen much worse. It doesn't look like the corrosion is focused where contact is made.
Check the buss bar connector for the controller board for the sense wires and the socket. If you have corrosion in the pins or connector . . . pin-to-pin leak . . . that might explain block 10. You might even try to clean the crap off the circuit board around the connector socket. Bob Wilson
I don't think it was the corrosion either. There is no corrosion where contact is made. It looks bad but its in an insignificant spot. Notice how bright the copper is under the contact nuts.
Well whatever I did in taking off all of the bars, terminals, nuts etc and cleaning them up seems to have made block 10 appear 'normal' in comparison to the other blocks, i.e. not the lowest voltage block on discharge and not the highest under charging. I still don't know if the fault is rectified until I use the car for frequent long journeys, since the error codes I initially had were only flagged during a long drive on the motorway, but I am happy that during my brief discharge to 40% and charge back upto 80% that block 10 appears much better while monitoring on Techstream. There was corrosion under the nuts, like a green opaque film. Almost like the green threadlocker that is available. Corrosion was also visible on the back side of the main battery isolator terminal lugs, which I believe are used as the link in block 10. A few rushed photos don't show the whole picture. The main battery terminal lugs were also corroded on the back sides, as well as a white powdery residue on many of the battery sense ring terminals, between the copper and ring. I suppose that when we are talking in the region of 0.001 ohm differences then any corrosion is not good.