Tesla Inc. will need to fix almost every car it’s ever sold in China due to an issue with the vehicles’ acceleration systems.

Some 1.1 million electric cars that Tesla made at its Shanghai factory or imported into China between January 2019 and April this year will need to be sent an over-the-air software fix to rectify the issue, according to a statement from the State Administration for Market Regulation on Friday.

The problem occurs when a driver takes their foot off the accelerator in order to slow down. When that happens, what typically occurs is the additional power starts getting transfered to the car’s battery to charge it up. This makes the rate of deceleration somewhat uncertain, and could increase the risk of collision and pose a safety hazard, China’s regulator said.

Because of this defect, drivers may mistakenly step on the accelerator pedal, thinking it’s the brake.

Tesla representatives didn’t immediately respond to a request for comment.

According to data from the China Automotive Technology and Research Center and Bloomberg Intelligence, Tesla sold around 1,129,055 cars in China from 2014 through March.

Tesla will also be required to send an electronic notification to drivers when they depress the accelerator for too long a period, according to Friday’s notice.

--With assistance from Linda Lew.