Tesla Model S Signature. Photo: Tesla Motors.

Tesla Model S Signature. Photo: Tesla Motors.

Tesla Motors Inc. is offering a software update for 29,222 2013 model-year Model S electric vehicles equipped with certain NEMA 14-50 (240 volt) Universal Mobile Connector (UMC) adapters.

During vehicle charging, the adapter, cord or wall outlet could overheat and pose a fire risk, the National Highway Traffic Safety Administration reported. Tesla will provide an over-the-air software update to remedy the problem. Additionally, Tesla will mail affected Model S owners a replacement NEMA 14-50 adapter that’s equipped with an internal thermal fuse. 

Some vehicle owners have already received the software update, which allows the Model S onboard charging system to detect unexpected fluctuations in the input power or higher resistance connections to the vehicle. If these conditions are detected, the onboard charging system will automatically reduce the charging current by 25 percent.

“This fully addresses the issue by substantially reducing the heat generated in any high resistance connections outside the vehicle,” Tesla said in a released statement. “This update increases robustness and safety considerably in the unlikely event that a home wiring system, receptacle, adapter or cord is unable to meet its rated current capacity.”

To make sure they’ve received the updated software (version 5.8.4), Tesla Model S owners can check the vehicle’s center information screen.

Vehicle owners can reach Tesla at (877) 798-3752.