This experiment is based on a user scenario involving a vehicle that is already out of warranty and has shown signs of the BMS a079 symptom. The approach focuses on keeping the vehicle operating as stably as possible for as long as possible, while accepting a certain level of inconvenience. It has now been eight weeks since the BMS a079 symptom was first detected. So far, the BMS a079 error code has not occurred even once. Around the third week, the battery condition showed s

This experiment is based on a user scenario in which a vehicle that is already out of warranty shows BMS a079 symptoms, and the owner tries to continue using the car as stably as possible while accepting a certain level of inconvenience. It has now been five weeks since the BMS a079 phenomenon was first detected. So far, the BMS a079 error code has still never appeared. At around week 3, the battery condition worsened slightly. So, we limited the charging level to 60% and cap

This experiment is based on a user scenario in which a vehicle that is already out of warranty shows BMS a079 symptoms, and the owner tries to keep using the vehicle as stably as possible while accepting a certain level of inconvenience. This is the third-week result since the first detection of the BMS a079 phenomenon. So far, the BMS a079 error code has not actually occurred. In last week’s middle graph, the cell voltage deviation widened up to 0.09 V. Starting this week, h

This is the second week’s result since the first detection of the BMS a079 phenomenon last week. So far, the BMS a079 error code has not yet appeared. As shown in the left graph, even under the same charging conditions, the maximum cell deviation remains around 0.05 V, similar to last week. However, in the right graph, the maximum deviation has increased significantly to about 0.08 V. This difference is also clearly visible in the statistical data. While it’s possible to redu

Although we have analyzed numerous user datasets and real-world cases, this is the first time we have personally observed the same issue on our own vehicle. This gives us a valuable opportunity to study the problem not only from the developer’s perspective but also as an actual owner experiencing it firsthand. To share some background: the vehicle was purchased used in June of last year with about 120,000 km. It has mainly been used for development, and the annual mileage is

As many of you may already know, Tesla’s manual recommends limiting regular use of NCA/NCM batteries to 80% state of charge. The...

This method is intended to reassure owners who may be worried about BMS a079 even without visible symptoms, and to help used car buyers...