Loss of steering control

Summary

On July 28, 2023, the Office of Defects Investigation (ODI) opened a Preliminary Evaluation (PE23014) to investigate instances of loss of electronic power-assisted steering in MY 2023 Tesla Model 3 and MY 2023 Tesla Model Y vehicles manufactured by Tesla, Inc. The complaints allege a sudden and unexpected inability to turn the steering wheel or an increase in effort required to turn the steering wheel. These conditions were alleged to occur both during the drive cycle, at various speeds, and at vehicle start up. Consumers reported receiving the warning message “Steering assist reduced” either before, during, or after the loss of steering control, and some consumers described their steering begin to feel “notchy” or “clicky” either prior to or just after the incident. On February 1, 2024, PE23014 was upgraded to EA24001 to further investigate the alleged defect in the affected vehicles. Tesla identified the cause of the increase in steering effort as an overvoltage breakdown (the voltage applied exceeds the maximum design limit), which can overstress motor drive components on the printed circuit board of the vehicle’s steering Electronic Control Unit (ECU). If the primary motor drive components experienced an overvoltage breakdown occurrence while the vehicle was traveling above 0 mph, electronic power-assisted steering would be diverted to secondary motor drive components. The secondary, or backup, motor drive components would maintain electronic power-assisted steering until the vehicle reached 0 mph. If the vehicle was operating on the secondary system and reached 0 mph, the driver would lose electronic power-assisted steering with manual steering remaining available. Only manual steering would remain until the vehicle’s steering ECU is replaced. On February 19, 2025, Tesla filed safety recall 25V092 to address the loss of electronic power-assisted steering. The recall filing documents state that a steering ECU software update, identified as 2023.38.4, was introduced into production vehicles and provided to affected fleet vehicles through an over-the-air (OTA) update beginning in October 2023. The updated software was designed to prevent overvoltage breakdown and overstress of motor drive components on the printed circuit board. ODI’s analysis of related Vehicle Owner Questionnaires (VOQs) and Tesla field data found that complaint traffic declined following the 2023.38.4 software release. In view of the recall action taken by Tesla, ODI is closing this EA. ODI will continue to monitor the effectiveness of the remedy as is consistent with the Agency’s authority and practice.  NHTSA reserves the right to take additional action if warranted by future circumstances. To review the ODI reports cited in the Opening Resume ODI Report Identification Number document, go to NHTSA.gov.

Vehicles under investigation (2)