High Voltage Battery Requires Service (Acceleration and Charging Reduced)
The TESLA-BMS_A068 (Tesla BMS (Battery Management System)) EV fault code means: High Voltage Battery Requires Service (Acceleration and Charging Reduced). This is a serious severity code.
- Keep driving?
- Yes, but fix soon
- DIY difficulty
- expert
- Estimated cost
- Diagnosed and quoted by Tesla service; depends on the internal battery condition found. Battery-related repairs may be covered by the battery and drive unit warranty (8 years on current models, with mileage caps that vary by model) — check your coverage before paying out of pocket.
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Common Symptoms
- Alert on the touchscreen: "High voltage battery requires service — Acceleration and charging performance reduced"
- Top speed reduced and slower response to acceleration requests
- Reduced maximum range
- Charging takes longer than before
Probable Causes (Ranked by Likelihood)
- A condition internal to the high-voltage battery pack that is limiting the battery's performance (Tesla's official description — the specific internal cause is determined at service) Likely
- Firmware-level alert name (BMS_a068_CAC_Imbalance_Limp, per tessie fleet data) indicates the internal condition is a capacity imbalance between cell groups severe enough to trigger a performance-limiting limp state Possible
Step-by-Step Diagnostic Procedure
BMS_a068 is a step beyond BMS_a067: the internal battery condition is now limiting driving performance (top speed and acceleration), not just range and charging.
There is no owner-serviceable component — high-voltage pack work is Tesla-service-only. Per Tesla's official guidance, schedule service at your earliest opportunity.
While the alert is present, Tesla recommends keeping the battery charged to 30% or higher so the displayed range estimate stays aligned with the actual charge level.
Without service the vehicle may continue to show reduced power, acceleration, range, and charging performance.
Frequently Asked Questions
What does BMS_a068 mean on a Tesla?
Tesla's official meaning: the vehicle has detected a condition internal to the high-voltage battery that is limiting its performance. You may notice reduced top speed, slower acceleration, reduced range, and slower charging. Service is required to restore full performance.
Is BMS_a068 safe to drive with?
Yes — Tesla's official guidance is that the vehicle is OK to drive, with service scheduled at your earliest opportunity. Expect reduced power and acceleration until the battery is serviced.
What's the difference between BMS_a067 and BMS_a068?
Both indicate an internal high-voltage battery condition limiting performance. With BMS_a067 the effects are mainly range and charging speed; BMS_a068 additionally reduces top speed and acceleration, which is why Tesla words its service recommendation more urgently.
Sources
This page is built from documented references. Verify against your own service info before repair work.