NHTSA Expands Investigation into GM Braking System

By Katherine Hamilton

The National Highway Traffic Safety Administration is expanding its investigation into GM's electronic braking system after receiving several complaints.

The administration's office of defects investigation opened a preliminary evaluation in April after receiving complaints about a loss of brake assistance in 2023 MY Cadillac Lyriq vehicles.

The NHTSA is opening a further analysis after receiving more complaints to assess the safety-related consequences of a failed eBoost system when braking. The agency is also expanding the scope of its investigation to encompass all GM vehicles that use the system.

The complaints allege a hard brake pedal, followed by a "Brake System Failure" message at start-up or while driving.

Since opening the evaluation, the agency has received more reports of loss of brake assist, some of which have described issues inconsistent with GM's description of a spindle failure.

GM has stated that in the event of a spindle fracture, anti-lock brakes, stability control and traction control remain functional until the vehicle comes to a complete stop.

The driver reports allege an immediate loss of brake assist functionality instead of the loss occurring after the vehicle comes to a complete stop. The sudden loss of brake assist during braking could result in extended braking distance, the NHTSA said.

Write to Katherine Hamilton at katherine.hamilton@wsj.com

(END) Dow Jones Newswires

August 24, 2026 07:29 ET (11:29 GMT)