BMS_f149
BMS_f149_SW_precharge_too_short
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.
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.
Other BMS Codes
Tesla alert codes sourced from the community-maintained Tesla Alerts Dictionary. This information is for educational purposes only. Always consult Tesla Service for official diagnosis and repairs.