General Motors electric vehicles, including models produced in partnership with Honda, are facing heightened scrutiny from the primary US auto safety regulator. This follows hundreds of reported incidents, over 20 crashes or fires, and at least six injuries linked to brake problems.
The National Highway Traffic Safety Administration (NHTSA) began its investigation in April 2024, initially focusing on 2023 Cadillac Lyriq vehicles. The agency's Office of Defects Investigation (ODI) announced on Monday that it has escalated this probe to an "engineering analysis," which is the highest level of investigation performed by ODI.
The brake issues may affect more than 1 million vehicles, including non-EV models such as the Chevy Colorado, GMC Canyon, Buick Enclave, and Envision. Initial complaints often described a "Brake System Failure" message upon starting or after stopping. While GM linked the problem to fractures in the spindle of its "eBoost" brake-by-wire system, ODI has continued to receive reports of a loss of braking assistance inconsistent with GM's explanation.
These additional reports detail an "immediate loss of brake assist" while drivers were actively braking, which the safety regulator stated "could result in extended braking distance, which increases the risk of a crash or injury." ODI plans further analysis of potential failures within the eBoost system, which was introduced in 2019 and is used in popular EVs like the Blazer EV, Equinox EV, Cadillac Lyriq, Honda Prologue, and Acura ZDX.