Wang Hua, general manager of Xiaomi Group’s public relations department, issued a statement in response to the brake failure of Xiaomi SU7.

It has been reported that the problem has been resolved

For those who don’t know, the SU7 vehicle was towed to the Changsha service center in the early morning of May 9. Store personnel inspected the vehicle and reported that there was no mechanical failure/damage to the brake system. After running the “self-test” program, the brake failure warning disappeared and the vehicle started normally.

Wang Hua stated that this was indeed a software misidentification. He added that the problem has been resolved and there is no need to panic about the safety of the vehicle. He contacted an engineer from the automotive department to solve the problem. This is what happened to the car.

Xiaomi SU7’s main braking system was mistakenly identified by the software

The analysis confirmed that the vehicle’s main brake controller (DPB/BCP) system was “misidentified and failed.” It initiated the auxiliary braking method and the Auxiliary Brake Controller (ESP/BCS) began to respond directly to brake and decelerate the vehicle. At the same time, the brake system malfunction was also visible on the vehicle’s large screen.

When the backup braking system is used, ESP draws brake fluid from the DPB to increase the brake pressure at the wheels to stop the vehicle. As the ESP drew brake fluid from the DPB, the pressure in the master brake cylinder dropped rapidly and the driver could feel it while pedaling.

As the brake system switches between primary and secondary, the output pressure in the master brake cylinder drops to 0. But the SU7 never loses full braking power. Fortunately, ESP managed to take control of the situation and lose control of the vehicle.

Although the vehicle returned to normal, the user was offered a return/exchange of the vehicle. Xiaomi Auto was also ready to cover the expenses related to the return/exchange of the vehicle.