I commute about 40 miles on freeways each way. When the car really gets FUBAR, it only happens on the freeway... I have to hope and pray there is a shoulder I can pull off on when it does happen! It seems like the more I narrow down my parameters on the Car Scanner app, the less this issue happens? It also seems to clear the low voltage error faster if I turn the car off and back on again. To me it seems more like a BMS issue more than an actual cell issue?
I'm having the same problem or one similar. It happens at random intervals and and lasts between 10 and 30 seconds. Mine is a 2020 Kia Niro EV EX Premium, bought "Certified Pre-owned" which apparently means nothing of substance. It currently has 42k miles. I have replaced the 12v battery with no improvement. City Kia of Greater Orlando refuses to give me a loaner vehicle despite the safety concerns, and refuses to put that in writing, because they lack the spine to stand by their reckless decisions. I have a case open with Kia Corporate, but they deferred to the dealership and said to give them 7 days to reply. Any and all advice is appreciated.
So after dealing with this for a while and trying to narrow down any direct causes for the faults, I finally gave in and took it to the dealer. Initially the dealer came back and said it needed a new HV battery but is now saying that KIA wants them to exchange a wiring harness. Harness is supposed to be installed today- has anyone else had a wiring harness actually be the cause of these issues? Any updates Merrick? Lindar?
Until very recently the issue had vanished. It happened again the other day in the rain. I'm glad to hear that others are getting work done about it, no dealer within 100 miles of me will even try to diagnose it. With no stored error codes and no official communication from Kia they pretend like there's nothing they can do.
Picked up the car yesterday, all seems normal again. Drove it around at slow speed and at highway speeds for well over an hour with no recurring faults. Merrick, I think I was able to move the needle a bit by having data to back up my claims. I was very up front about there not being any OBDII codes and that they would have to read the codes from the BMS. Once they did that, they were able to pull a couple of codes including a differential voltage code (sorry I don't have the paperwork in front of me, so I don't have the exact wording) This kicked off the service line ticket with Kia and the new harness. About 2 weeks to get the car back. They are blaming the brakes pulling to the left on tires and were not "able" to reproduce the low speed clicking sound but I am hopeful I can drive the car without it shutting down.
I'm glad you seem to be out of the woods, it gives me some hope for the future. Mine gave a persistent cel only once. That was when I was able to bring it to Dyer Kia in Florida. All other times they have refused to check anything else. None of the dealerships here have staff willing to *try* anything. If you can, please send me what your dealer wrote up as work performed. It will help send them in a direction. Whether they actually move in that direction is another story
During the test, I would assume the tech got the light to come on because it does say the warning light on... Right before I took it in the problem got way worse with a couple of variables that may or may not factor in since it was always so intermittent. Less than 30% battery and slow speed driving, under 30 MPH. My problem was very intermittent but 99% of my driving is highway. I ended up driving some surface streets with low speed limits a couple of times right before I took it in and I wasn't sure I was going to make it home a couple of times! I took to the dealer at about 50% charge, several of their test drives had averages of 4, 6, and 20MPH averages (do they know of this problem?) Fastest drive I show when they are troubleshooting was 29MPH average speed over 50 minutes. Anyways, when the turtle light was on they scanned for codes and got BMS P1B9600 High Voltage Battery Cell Deviation. Tech Line case opened- Replace 37561R1H Volt & TMEP Sensor Wiring Harness R&R(I assume this is a mistake and should be Temp)- This I think is the shop process 37517-Q4001 Wiring Harness - BMS *This is the actual part* They do have to remove the battery tray to make this swap and includes the coolant lines, battery cover, HV connector disconnect, etc. https://www.kia.parts/oem-parts/kia-wire-harness-37517q4001 Not sure if it is allowed or not but when I Googled the BMS trouble code I got this- https://www.speakev.com/threads/eniro-limited-power-error.163683/page-6 I am hopeful but not 100% now...
I'm having the exact same problem! I've brought it to the dealership now 6 times. They've changed the onboard battery management system, but a week later the same power down turtle came up. Brought it to the dealership and they drove it all week, and can't make it happen again. It's so annoying there's no error message or anything recorded on the obd. I'm wondering if you can tell me the OBD2 device you used and app. I'd like to trace which battery the same way you did. I have an OBD device but it only gives a code. Thanks so much for your help. It nice to know other people are having this issue.