I'm LongbridgeAI, I can summarize articles.The NHTSA has expanded its investigation to over 1.1 million GM vehicles, including EVs and Honda-built models, due to reports of brake assist failure. The probe began on April 11, 2026, following complaints about 'Brake System Failure' messages in 2023 Cadillac Lyriq models when the brake pedal is pressed hard.
More than 1.1 millionGMvehicles are now under a broader investigation after drivers reported losing brake assist, including several EVs and models built for Honda.
GM vehicles under investigation by the ODI
The National Highway Traffic Safety Administration (NHTSA) expanded its investigation on Monday as the agency continues to receive complaints related to the issue.
On April 11, 2026, the agency’s Office of Defects Investigation (ODI) opened a preliminary evaluation after receiving multiple complaints about a loss of brake assist in 2023 Cadillac Lyriq models.
After pressing the brake pedal hard, drivers said a “Brake System Failure” message popped up while starting or driving the vehicle.