Hi...I have an amateur's working knowledge of how the hybrid batteries work and have successfully replaced a failing module before. But a year later, I've replaced another bad module twice yet am still getting all the warning lights on the console. I'm stumped? Any help would be hugely appreciated. Here's a chronological timeline of warning lights and my repairs so far and have attached screengrabs from Dr. Prius app of stress tests after the original failure, after the 1st replaced module, and after the 2nd replaced module: 1. Got hybrid battery warning lights. Did a stress test and got readings thru Dr. Prius app. voltage diff was .93 - it showed block #7 was bad. 2. Removed the entire pack from car, did individual voltage test on each module. Indeed module #13 in block #7 was 1.2 lower than the rest. 3. Replaced bad module with a replacement one I got from reputable source. Reinstalled the pack into the car. No warning lights. Took for a drive and a few mins later got hybrid warning lights again. 4. Did stress test - only have the charging screengrab? but it showed .78 diff again with block #7. 5. Removed entire pack from car again. Tested the individual modules. #13 was again low? I charged them all to the same voltage and returned the next morning and checked voltage, #13 had dropped from 7.90 to 7.38? 6. Assumed the replacement module I received was the problem. So ordered a 2nd replacement module. I swapped the 1st replacement mod with the 2nd, charged it to match the rest of the modules. Reinstalled the pack into the car for the 2nd time. 7. Started the car and no warning lights. But again, drive a few mins and got warning lights. 8. Did a stress test thru Dr. Prius app and again it showed during charging block #7 had a 1.08 when charging diff and a .24 diff when discharging. Again i'm stumped? I doubt that both of my replacement modules are bad? And when I reassembled the pack I took my time, made sure it was done to spec. What am I missing here? Cheers!
The other identical thread has been reported so the moderator can remove it. So this is the real one. Not being a fan of individual replacements, and therefore not very experienced, what I do know is that you can't expect very good results unless you balance the battery after replacing part of it. And keep in mind that the modules you don't replace are just as old as the one(s) you do replace and will probably fail soon as well. Others will hopefully be here soon with more detailed informtation.
Have you asked the car yet why the lights are on? The diagnostic codes help a lot. If you haven't, it's anybody's guess whether it's even about the battery.
The Dr. Prius app can read any codes you might have. Some comments on your Dr. Prius images: They show IR of 19 mΩ which are the default values and of no help until they recalculate to the actual values. Both your charge and discharge currents are quite low with the maximum being a charging current of 6.65 V. The graphing on Dr. Prius is terrible and grossly exaggerates (visually) the extent of the imbalance between modules. A module in block #7 still is a problem. You mentioned "stress test", does this mean force charging and then holding the car in reverse with the parking brake fully set (discharging)? It is not really a matter of "good" or "bad". It really (really) matters how the replacement module matches the other 27 modules. This is in fact the hardest part of what you are attempting to do. You can get a relative comparison of all the modules by doing a load test on each one. You probably need to recondition all the modules and then reevaluate how well they match if you really want the best chance of success. Bear in mind that even the most perfect job you do will only give you an 18-24 months extension at best. Start planning to replace all the modules with either a set of new ones or a relatively new (i. e. < 5 yo) set from a recent wreck.
Voltage on the block is nice but what’s happening here is that battery will not supply rated current. Soon as you put a load on the soft modules it will tank the ecu sees that and says nope. The modules you are buying are of the same vintage you have maybe older these are not new modules and have probably been fluffed up so they last A little while. It’s a real crap game and module testing on your end is useless without a load test. you are deep into the whack a mole.
or just replacing the wrong module.... How are you counting blocks? Where is block 1? Or maybe Block 6 is pretty sketchy also? 18.16 volts?
Diagnostic codes are five-character symbols; they look like P0A80, for example. On PriusChat, we can usually help more when the post says what the actual codes are from the car, rather than a paraphrase.
thanks for the response.... when I swapped the module I charged all the modules to match either others voltage...approx 7.9. i did the same the last module swap I did last year and I did the trick. is that what you mean by "recondition" ? something tells me recondition is a more involved process as far as load test on each module...yes i've seen load test rigs with a litttle light wired into the tester.
whack a mole/module. lol. so right the load test which is what other commenters said. u mean individual module load test?
any idea where one can buy a load tester for something like this? i'm not super technical so would love to just find one ready to go? cheers
Theirs hundreds of posts about battery re builder setups please use the search forums link up top and search hybrid battery
Or maybe Block 6 is pretty sketchy also? 18.16 volts? Slowly leading the horse to the water pond............
"Not super technical" + HV battery = paying some one else to fix your car. Sorry but no way around that. Just replacing a module or two almost never works. Either educate yourself about the whole DIY process (which will take weeks to perform and might get you a year or two if it works well), or purchase a complete pack and install it. Posted via the PriusChat mobile app.
I successfully replaced a dead module over a year ago and it solved the issue and ran great for 10k miles until now. swapping not a long term solution but would love to get another 8-12 months out of the car. cheers
block 1 is on opposite side from ECU. good spot on block 6. ill do a stress test on them all and see what I find. cheers
