Has anyone got the BMS_a079 alert?
Vehicle info: Model Y AWD (4680 Battery Pack) Picked up in April, ~1300 miles
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Vehicle info: Model Y AWD (4680 Battery Pack) Picked up in April, ~1300 miles
i took it in to tesla, and all they did was did a hard reset to fix it. all you have to do is lift your backseat up and unplug the harness under the rear right side for 3 mins, then plug back in, and fix. youre welcome all. software glitch by the way
Yes, thank you indeed. This saved my ass. I was getting the error and was below 40% and I did the cable thing you described and everything is fine now I’m still keeping my appointment for service two weeks from now so they can check everything out, but I just went from being unable to charge to going to 90% at a supercharger. You’re a hero.
It's been about 9 months and my battery is still fine. I'm glad i can help you. I just hope tesla doesn't make stuff up like you need a battery replacement.
Yo. Mind if I ask if all was good after a year we have an appointment for our MY but if this is an easy fix I can do it myself.
Yes mines is still good. Never happened ever again. I guess I got really lucky
My wife’s model Y didn’t look like the pictures and we were able to get her car in early and they are replacing the HV battery. Good news is they gave her a Model S plaid for a week while they replace it.
Mine went wonky again. Your fix clears it for a day but my battery really is going south and the online techs verified other codes that point to the battery. To the shop it goes
Did the code ever came back for you?
Yes. I had to do the reset thing three or four times until I could get a Tesla service appointment. They ended up replacing my battery in warranty. But without this little cheat, I could not have gotten my car charged up a few times and it would’ve just been dead in the driveway so thank you for that.
What did you do exactly? I'm having this issue while on a trip
Parked. Removed backseat bottom (pops up with a tug or two) and disconnected the large electrical connector that connects to the aluminum floor below the seat. It is a really fat connector and it has a plastic lock lever. Disconnected for 5 minutes and reconnected.
I ended up needing a new battery but this can get you out of a jam if you are on the road and needing to charge.
Perform at your own risk. No warranty or guarantee expressed or implied.
How many miles were on your model? Out of curiosity, I’ve been getting the same error and I’m under 100k
Can you describe the cable and if possible find a pic of it? I’m a little confused as to what he meant by “harness” since I have to connections, one is red with a positive sign and has a bolt and the other one is just a black one made of plastic.
Thanks, this happened to me while on a road trip and you saved my trip! Appreciate you
Did it ever happened again?
Yeah, it came back after a while, took it to a service center, and I needed a battery replacement. Your tip still help us get through the trip.
I’m confused on what “cable” or “harness” to unplug
+1 for working on my 2020 MYLR. Thank you!
What part of you disconnect? The ground or positive or both?
Is it the black harness on top of the battery pack under the right rear passenger seat?
Thank you for the great tip. This site gave visual instructions that I needed: https://www.mountainpassperformance.com/tesla-model-3-hard-reset/
I was cautiously optimistic, but this did not work for me. Headed to the dealership on Monday. Thankfully I'm still under warranty.
Thank you!
Did you get the same error BMS_a079?
Yes I did get the exact same error code and it's gone now after the harness unplug and replug
That's interesting. To me, Service Center rep told me, they did the diagnosis and battery change is required. I wonder if they even looked at it. My Model Y seems to be parked at the same location when I took it there, which was 2 weeks ago.
In the the app, repair progress notes does not say anything about steps taken. It only says charging(preparing) and tire pressure check(preparing), those are the only steps which have been there since the beginning.
You can request your car back and unplug it yourself. I googled it and it seems it works for others as well. The glitches happened right after the recent update
Thanks for the information. I wouldn't mess with brand new car under warranty. But I will tell the SC rep about what you suggested. Thanks again.
Please keep me updated if it worked out for you
I checked with SC. No updates yet. I also informed them about your suggestion of hard reset. No response yet.
Its almost 3 weeks in service center.
I see. Well, hopefully, they can just do a hard reset by unplugging the negative on the battery or just unplugging that harness for 3+ minutes, instead of changing out the battery.Yeh if I can attached an image to show you that I had the exact same code, I would; Unfortunately, reddit won't let me attach any images. Fortunately, it's been 9 days already and the code is still gone and hopeful stay gone
They did respond yesterday. Said they have not worked on it yet. It is in the queue and they are overloaded. They told me to have patients.
Yes then a day after more alerts ended up with a new battery pack.
Really hoping it doesn’t come to this but thanks for the info!
Alert first appeared when the 2023.20.4.1 update was available. It disappeared after the update was installed but reappeared today after a short drive.
Any information is appreciated, thanks.
Schedule a service appointment, they will be able to quickly diagnose it remotely.
Thanks! I just did but I’m wondering if this is something serious lol
It could be serious. 4680 are new, so there will be issues, especially in early production like now
Isn't it a structural battery pack, wonder if battery replacement is even possible 🤔
Really hoping it’s something minor
Hope it's just a software issue 🤞
I got my battery replaced for this same error message. Got car back today
I had the exact same thing happen to me and reappeared after the update. The SC can't see me until the 3rd.
I asked Tesla for expedited service (via Messages under Upcoming Appointment).
They replied saying for these alerts, they recommend bringing the car to a service center immediately and that I can use Roadside Assistance to arrange a tow.
My earliest appointment is Jul 10 but I will be bringing it in later this week.
They told me I can tow it in if "I'm uncomfortable driving it". They didn't say if it could be looked at earlier. I'd keep driving it, but I have no idea what the new maximum charge level is. Every time I plug it in, it just says charge complete. I'd rather not get stranded while I'm hauling my disabled spouse and her wheelchair.
This can be one of two things:
A glitch requiring a software update
Replacing the battery pack due to a fault (Hopefully it doesn't come to this.. :(
Your best course of action is to always open a service request with Tesla. Especially if the vehicle is under warranty.
I did a service request and a rep replied I should bring the car in asap, no appointment needed.
Yes, same alert came on my month old Model Y last week. It won't charge anymore. They took it in service and gave me loaner (2018 Model X). Apparently, you can only loaner within 200 mile radius from service center.
For now they have given me the date as 7/21/23. But they said it could take longer.
Vehicle info: Model Y AWD (4680 Battery Pack) Texas Made Picked up May 20th
Update: I reached out to Tesla Service Team with 200 mile radius question for loaner. Rep said (responded immediately), no issue of milage. I can take longer drive trips. Apparently super charging on loaner is also free.
Update: Apparently, Progressive insurance does not even cover loaner given to me by Tesla service center. So loaner is basically useless. Tesla reps told me, I am on my own for arranging my transportation.
Update: I had returned the loaner. But I called Progressive again and explained the situation. They said, under the circumstances they will cover the loaner. So I got the loaner Model X back. Tesla service team was very happy to help.
Looks like recent model have this issue or what. On this tread we 3 or 4 people all are recent buyer with mileage in 1k are having this issue.
Thanks for your info, unfortunately I won’t be able to bring my car in till later this week so if you could share what Tesla finds out will be greatly appreciated.
The only good thing I guess is that I’m only 30 miles away from a center.
Yes, I will keep updating on progress. No word on Model Y yet. However, so far, service team is responding very quickly with any questions I have.
I got same message of error code BMS_a079 yesterday. Mine is model Y AWD standard picked on 7th June with only 1000 mile on odometer. This is really disappointing that a brand new car having such glitches. Took to service center for walk in and they gave a model 3 loaner. They will provide updates once their diagnosis completed. On search on internet it seems battery change required but just same message above that could be a harness issue. Hope it doesnt require a battery change.
Sorry for the late update but I hope this helps.
TLDR: HV Battery is bad and got it replaced under warranty. New battery is working just fine.
Long version:
Jun 24 - Error appeared (2023 Model Y AWD 4680 Battery Pack with ~1300mi)
Reached out to Tesla immediately and received a response soon saying that for this type of error I can just head to my nearest service center (no need to schedule a service request in the app)
Jun 27 - Brought my car to a service center, received a loaner
Jun 28 - Service advisor said the HV battery is faulty and will need to be replaced. However that particular battery was not in stock and had to be ordered
Jul 9 - Received notification that my car is ready to be picked up
Jul 10 - Went to pick up my car after working hours and found some genius left his car parked in front of mine
Jul 11 - Actually picked up my car lol
How's the new battery pack on your car?
It has been working fine after the original one was replaced
Thanks for your info, unfortunately I won’t be able to bring my car in till later this week so if you could share what Tesla finds out will be greatly appreciated.
The only good thing I guess is that I’m only 30 miles away from a center.
Update - Tesla service center informed me that they will need to replace the battery. Battery is the most important and expensive part of EV. This is not a good sign
Hey just wanna thank you again for providing all the updates. It helps me a ton and I’m pretty sure people in the future will find this helpful too lol.
I am having a really bad tooth ache so I put my MY issue to the side for now. Trying to bring it in tomorrow and let’s see what they say.
Just got it, 2021 Model Y long range, 49k miles. Service apt scheduled.
Battery replaced on mine. Dropped the car off at the service center late on a Thursday and picked it up with a new battery on the following Monday.
This happened to me yesterday. 2021 MYLR with 44k.miles. Took the car to tesla SC. Within a few minutes of service request, I got messages that they placed an order for HV battery replacement. So, don't think they are waiting for any initial diagnosis or hard reset, etc. mentioned by others, to resolve this issue.
Just got this alert today on my 3 month old Model Y. Can u share what the the service center said and resolution they provided? Thanks
Got this at the weekend when I was 300km from home in a regional area. Towed back to my local service centre and battery being replaced
I just got the same error this morning 2021 model y lr 70k miles
Did they replace yours under warranty ? Just got this message on my 2021 model y 55k miles. Paid for extended warranty but that doesn’t cover battery issues
I am sorry this happened to your car, hope it is good now. I added my experience as an update just now.
The main battery can just have issues but look on the bright side.. your new battery will probably have more range than the old one. I wouldn’t stress too much. I have had 3 teslas and one had one issue…the front motor died at 1600 miles…and after then it was flawless. The others have had no real issues. Driven about 75k miles now on the 3 combined.