VCLEFT_a478_LVBMS_MOSFET_Open
Low voltage battery service is required
What does the VCLEFT_a478_LVBMS_MOSFET_Open alert mean?
The low voltage battery management system (LVBMS) has opened the low voltage (LV) battery's internal protection transistor (MOSFET), disconnecting the LV battery from the rest of the vehicle electrical systems.
What you'll see in your Tesla
- Low voltage battery service is required
- Schedule service - Vehicle may not restart
What triggers it
The LVBMS reports the LV battery's internal protection transistor (MOSFET) is open.
When it clears
The LVBMS reports the LV battery's internal protection transistor (MOSFET) is closed again.
Potential impact
The LV battery is unable to support vehicle electrical systems or to recharge via the power conversion system (PCS). The high voltage (HV) system will remain energized to continue supplying electrical power to the vehicle while the LV battery is unavailable. This may result in greater range loss than expected, increased HV system energy consumption when the vehicle is idle, and prevent the vehicle from sleeping.
Affected models
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