BMS-F121
BMS_f121_SW_BMS_PCB_HumiditySens
Also written as BMS_F121 / BMS F121 / BMS_f121_SW_BMS_PCB_HumiditySens / bms_f121_sw_bms_pcb_humiditysens
Why does the exact Tesla alert ID matter?
Record the exact alert ID, including underscores, suffixes, and companion alerts. Tesla alerts that look similar can point to different modules, timestamps, and service procedures.
What does BMS-F121 mean?
Tesla fault code in the Battery Management System (BMS) module. The Battery Management System (BMS) Printed Circuit Board (PCB) humidity sensor is giving an implausible reading.
Original Description
The Battery Management System (BMS) Printed Circuit Board (PCB) humidity sensor is giving an implausible reading.
Affected Tesla Models
What You May Notice
- Red warning light on dashboard: The Battery Management System (BMS) Printed Circuit Board (PCB) humidity sensor is giving an implausible reading.
- Vehicle may refuse to drive or charge until the fault is cleared
- Sudden power reduction or shutdown may occur while driving
How to Diagnose and Resolve
- 1 Stop driving immediately and move to a safe location
- 2 Do not attempt to charge the vehicle — active fault: "The Battery Management System (BMS) Printed Circuit Board (P"
- 3 Call Tesla Roadside Assistance (+1-877-798-3752) for a flatbed tow
- 4 At the Service Center, Tesla technicians will inspect the HV battery pack and BMS firmware
Severity Notes
BMS-F121 is classified as a Fault, indicating a critical issue in the Battery Management System system. Do not continue driving and contact Tesla Service immediately.