BMS-F149
BMS_f149_SW_precharge_too_short
Also written as BMS_F149 / BMS F149 / BMS_f149_SW_precharge_too_short / bms_f149_sw_precharge_too_short
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-F149 mean?
Tesla fault code in the Battery Management System (BMS) module. The Battery Management System (BMS) detected that the length of time it took the vehicle to precharge was too short. During the precharge sequence when the BMS is closing the contactors, the time it takes to reach target precharge voltage is too short. If the DC link voltage rise does not match a time constant with a 35% tolerance, then a precharge fault shall be asserted and precharge will be aborted. The precharge being too short means that the voltage on the DC Link bus (vehicle side of contactors) rose faster than expected, similar to how if there was not enough capacitance on the bus.
Original Description
The Battery Management System (BMS) detected that the length of time it took the vehicle to precharge was too short. During the precharge sequence when the BMS is closing the contactors, the time it takes to reach target precharge voltage is too short. If the DC link voltage rise does not match a time constant with a 35% tolerance, then a precharge fault shall be asserted and precharge will be aborted. The precharge being too short means that the voltage on the DC Link bus (vehicle side of contactors) rose faster than expected, similar to how if there was not enough capacitance on the bus.
Affected Tesla Models
What You May Notice
- Red warning light on dashboard: The Battery Management System (BMS) detected that the length of time it took the vehicle to precharge was too short. Dur
- 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) detected that the length"
- 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-F149 is classified as a Fault, indicating a critical issue in the Battery Management System system. Do not continue driving and contact Tesla Service immediately.