MyTeslaMate
BMS family

BMS_a099_SW_BMB_Communication

Not Available

What does the BMS_a099_SW_BMB_Communication alert mean?

The battery management system (BMS) cannot communicate with all of the battery monitoring boards (BMBs).

What you'll see in your Tesla

  • Not Available

What triggers it

A communication issue with the BMB daisy chain is detected.

When it clears

No communication issues with the BMB daisy chain have been detected.

Potential impact

This alert is primarily informational, and may indicate a loss of BMB sensor data

Affected models

Model 3 2017-2023 Model 3 2024+ Model S 2021+ Model X 2021+ Model Y Model Y 2025+

Track your Tesla's alerts automatically

Alerts like this reach MyTeslaMate through your car's Tesla telemetry API. MyTeslaMate logs every alert your Tesla reports and turns it into readable history and real-time notifications — hosted TeslaMate with no server to run.