Here is a list of common Tesla BMS (Battery Management System) error codes and their explanations:
BMS_u029: Maximum battery charge level reduced
This error indicates a high likelihood (95%) of a malfunction in the high-voltage battery. The vehicle may not reach a full 100% charge, and you may experience rapid charging and discharging cycles.
BMS_u018: Maximum battery charge level reduced
This error signifies an imbalance within the battery, where one or more battery bricks have lower or higher capacities than they should. A battery diagnosis is required to identify and replace the faulty bricks.
BMS_w164: Battery imbalance warning
Often accompanying BMS-U018, this error indicates a battery imbalance that could lead to total battery failure.
BMS_a079: Unable to charge – Maximum charge level reached
This error suggests an internal issue with the high-voltage battery, limiting its ability to charge beyond 50% of the State of Charge.
BMS_a068: High voltage battery requires service
This alert indicates a condition within the high-voltage battery that is limiting its performance. It may result in reduced top speed, slower acceleration, and decreased range.
BMS_a074: Maximum battery charge level reduced
Similar to BMS-A068, this error signifies an internal battery condition limiting performance, resulting in reduced maximum charge level and range.
BMS_w035: Vehicle may not restart
This warning suggests potential issues with the battery system that could prevent the vehicle from restarting.
BMS_f123: Internal isolation fault
This error indicates a serious internal isolation problem within the battery system.
BMS_w073: Unexpected high-voltage system behavior
This warning suggests abnormal behavior in the vehicle’s high-voltage system.
BMS_w142: Isolation degradation
This error points to a degradation in the electrical isolation within the battery system.
BMS_w158: Low isolation warning
This warning indicates a low level of electrical isolation in the battery system, which could lead to safety issues.
When encountering these errors, it’s crucial to contact a Tesla service provider as soon as possible. Many of these issues require professional diagnosis and repair to prevent further damage to the battery system and ensure the vehicle’s safety and performance.
If you are experiencing battery issues with your Tesla, consider module repair with a trusted provider like EV Doctor. Contact us today to schedule a diagnostic assessment and take the first step toward restoring your vehicle’s performance.