questions about rebuilding hybrid battery

If you attempt to repair the battery by replacing modules, make sure you replace 2 modules at a time (1 entire block). That way they will be somewhat matched and play nicely together. Also make sure you get yourself a proper pair of electrical gloves before taking the battery pack apart....your life depends on it.

 

Yes after replacing the failed modules you will need to charge and discharge the pack a few times to balance all of the modules to each other. A very easy way to do this is to the entire battery pack at once is with our charger and discharger system.

 

mom from Florida. Totally lost. I don't know what to do. Can someone help me with the HV battery?

 

Give us a call tomorrow at 800-589-0730. Our support team can educate you about the process.

 

You are about 100 miles north of @TampaPrius.com. Even if you can't get to him, give him a call, he will be able to advise you of your options.

 

Thank you! I just called and a rep at your office was very helpful.

 

jeff652 - any thoughts on the other question from MobileFleet - how close do the voltage readings need to be in each cella, to not worry about them causing problems? I've got a 2005 Prius with 209k on it, and just measured the voltage in all my cells. Varied from 7.86 to 7.89, with one at 7.74. Is that one cell different enough to cause problems? Thanks!

 

Doesn't really matter if there that close voltage wise what matters is there behavior under load. How fast does one module drain compared to others. They all have to be load tested to find the weak sister. All modules must be able to handle a load. Any weak one in that series chain and the whole chain fails. Thats the one the system see's and complains about.

That and corrosion on all the interconnect and the temp sensor lines and at the ECU connector/board..

if you had techstream it would tell you which module its unhappy about.

use search forum button up top. Search techstream

Thousands of posts about obd code readers that will work.

 

Also Android Hybrid Assistant software has quite good HV battery check feature what logs voltages during drive.
Pair it with some cheap OBD2 bluetooth reader and go for a run.

Same developer has Hybrid Report software what creates great graps from Hybrid Assistant logs.(here is mine from some time back w/o HV check Report_2018-05-12_10-01-51.html)

Those apps are great for logging all kind a stuff from car.

 

And those apps are free.

 

Thanks edthefox5 and qettyz. I ordered an obdII, a couple days ago, and while waiting for it to arrive, pulled the battery apart. Sounds like I jumped the gun, and the easiest way to determine if I have a bad module, and if so, which one, is to put it back together now, and use the computer and software.... At least I didn't pull it all the way out, since I only planned to test the modules, only pulled the top off, and one buss. There is some corrosion on the buss plates and nuts, but doesn't appear to be enough to cause issues at the moment. Thanks for the heads up on corrosion on the temp sensor lines, and the ECU - I'll check those out.

I got the red triangle, check engine, and yellow indicator lights, and the hybrid system warning light. The battery indicator has been acting strangely - going much more rapidly than normal from 8 bars, to 2, back to 7, down to 0, up to 10 even on flat ground. Transitioning over ~a minute, rather than the usual many minutes. Then it acts normal for 5 or 10 minutes... Only doing this for a couple days. Been a great car, only routine maintenance up to this point. One change of the 12v battery about 5 years ago. Not bad for 13 years and 209,000 miles.

I've got nobody in my small town that can run diagnostics on a Prius, and the closest shop I could find wanted $165 to do it. I'll be patient, and figure it out myself. Plan to use Hybrid Assistant or Dr. Hybrid. Are these as comprehensive as Techstream?

Thanks!

 

Yep
But nothing beats techstream.

 

Yeah Hybrid Assistant is way to check voltages on load, but Techstream is the software when you need to read codes and do more depth analyze.

 

Here is some graphs from my -14 Auris done with Hybrid Assistant. About 26k km on the clock. I bought it last august and it had only 11k km
Ive been monitorin block voltages since car was not driven much. First block 7 was the weakest many months, but now its switched to block 9. Yeah, some block is always weakest and im happy its not same anymore.

Edit: there is peak in first recharge because i was force charging it with break&throttle and stopped it for a little while and then back on causing that peak.