Unknown Error BMS_a066

[Ohhyunjin0207]

I was involved in a rear end collision (25-30mph collision from back, i was idle because the light just turned green) back in 10/15/2021. I just received my car from Diamond Hills Collision tesla certified body shop yesterday 12/22/2021. Everything was good until i drove the vehicle for about 100 miles after charging to 90% (AC, 7kW) and noticed an error message BMS_a066, Maximum battery charge level and range may be reduced. I called the body shop the next day and took it in for a scan but they said everything was fine. I have service center scheduled for 1/15/2022 which is couples weeks out and i can’t seem to find any M3 drivers having the same error code. Does anyone have or had this error code BMS_a066 before?
I’m lost because I’ve never gotten an error code before, only after I received the repaired vehicle yesterday.
I have a 2021 Model 3 SR+

 

[Msgabbb]

I got this on Christmas Eve and schedule a service appointment for today at 10:45. I will let you know what they say.

 

[Ohhyunjin0207]

I called tesla and they didnt know what it was so i just went to the nearest service center and thankfully they took it in. Within couple hours they called me saying that the car is trying to balance the battery and it should go away soon.
Ill follow up with an update next week and see if this goes away

 

[Superbyte]

Got the same error after installing the holiday update. Error went away on my next drive but I'm not taking any chances so I'm going to SC tomorrow and see what they say

 

[Ohhyunjin0207]

Im not sure whats going on, hopefully just a software bug but i constantly have reduced regenerative braking. Please update us! I’ll update frequently with my M3 SR+ status

 

[Superbyte]

Welp, not the good news I wanted to hear but they're replacing my HV battery so they offered a loaner in the meantime.

 

[Ohhyunjin0207]

Oh yikes, im gonna go back in if this error keeps popping up, so far everyday I’ve been getting this error

 

[lukeofthetauri]

FWIW- I had the same thing. Popped up after holiday update, scheduled service for Monday of this week and was told my new battery was arriving as I left with the loaner. I couldn't find any references to this error until this thread. I've got a 2018 Dual Motor 3.

 

[Superbyte]

Just speculating but maybe the holiday update introduced more diagnostics for the HV battery?

 

[lukeofthetauri]

That’s what I wondered- something they’d picked up on in failing packs and are doing this to catch them and replace them.

 

[Ohhyunjin0207]

I've been getting the same error almost everyday, so I scheduled SC appointment for 29th. I received an estimate from SC saying 12V Battery will be replaced.
Does anyone know that 12V Battery replacement is going to solve this issue?

 

[erober4]

I wanted to chime in with my experience. I got the warning on 1/12. It went away the next morning and then about 24h later it came back. It seems to only show up when the car has 50% or less battery and hasn’t been on the charger for a while. I made an appt with Tesla service (somehow got same day) they called me within a few hours of making the appt. They were able to diagnose the car remotely and ordered a new HV battery for the car. Estimated 3 weeks to get delivered. 2-3 days of work to replace the battery once it’s here. So far it’s been a very easy experience. I have a 2021 M3 SR+. It only has 12k miles on it.

 

[Superbyte]

Just got my car back from the SC for the HV battery replacement with warranty. I didn't have my car for almost a month so I'm glad I got a loaner early on. Wish they gave better estimates because it kept getting pushed week after week. Kind of got aggravating

 

[EZTider]

Got the error and scheduled service for tomorrow morning. 2018 M3 Dual motor.

 

[Ealopez29]

Just got the error code yesterday. I guess I’m getting a new pack? Lol. I’m at 96k miles right now. 2018 model 3 LR RWD

 

[chasemym3]

Just got the error code yesterday. I guess I’m getting a new pack? Lol. I’m at 96k miles right now. 2018 model 3 LR RWD

I just got the same error as well. Keep us posted!

 

[stozzer1]

Just had the error (bms_a066) pop up on Saturday, appointment scheduled for this week (although the fault disappeared on my way in to work this morning). Any info on what is actually wrong with the battery / management system? 2021 Model 3 Performance (4500 miles)

 

[stozzer1]

Just had the error (bms_a066) pop up on Saturday, appointment scheduled for this week (although the fault disappeared on my way in to work this morning). Any info on what is actually wrong with the battery / management system? 2021 Model 3 Performance (4500 miles)

Two new errors this morning bms_a064 & bms_a174 and the car failed to charge last night. Service Appointment is tomorrow, luckily I think I have enough charge to get me there.

 

[Chichiño]

HI;

Same error yesterday; M3P MIC

 

[Chichiño]

HI;

Same error yesterday; M3P MIC

Battery replacement on the way.... Only 6 months and 16800 km.