Federal safety regulators have opened an Engineering Analysis into roughly 1.16 million GM and Honda vehicles after their shared eBoost electric brake booster racked up 745 failure reports, 22 crashes or fires, and six injuries. The system can suddenly cut brake assist, ABS, stability control, and traction control — sometimes without any warning before the pedal goes hard.

Key Points

• The National Highway Traffic Safety Administration’s own investigation file, designated EA26006, upgrades a Preliminary Evaluation opened in April 2024 (PE24011) to a full Engineering Analysis — the step that typically precedes a recall decision.
• NHTSA counts 745 total incidents: 227 reported directly by owners and 531 identified by GM itself, according to Electrek’s reporting on the filing.
• Twenty-two crashes or fires and six injuries have been tied to the defect so far, with zero fatalities reported.
• The suspected root cause is a fractured spindle inside the eBoost brake module, which can trigger a “Brake System Failure” dash message and a suddenly firm, unassisted pedal.
• Some of the newer complaints describe brake assist cutting out mid-stop rather than only after the vehicle comes to rest, which NHTSA says could extend stopping distances, per CBT News.

What’s Affected

The eBoost system is shared across GM’s newest EV and hybrid architecture and two Honda-brand vehicles GM builds under a joint program. Per NHTSA’s investigation resume, the affected population includes:

• 2023-2026 Cadillac Lyriq
• 2023-2026 Chevrolet Colorado
• 2023-2026 GMC Canyon
• 2024-2026 Buick Enclave and Envision
• 2024-2026 Chevrolet Blazer EV, Equinox EV, and Traverse
• 2024-2026 GMC Acadia
• 2024-2026 Cruise Origin
• 2025-2026 Cadillac Celestiq and Optiq
• 2024-2026 Acura ZDX
• 2024-2026 Honda Prologue

That last pair is the reminder that eBoost isn’t a GM-only story: the Prologue and ZDX are built on GM’s Ultium platform and inherited the same brake hardware, which is why Honda and Acura owners are caught up in a GM-led investigation.

What Owners Should Do

• Run your VIN through NHTSA’s recall lookup tool — an Engineering Analysis is not yet a recall, so nothing may show up today, but that can change quickly if GM issues one.
• Pay attention to a firm or unusually hard brake pedal, a “Brake System Failure” warning, or any loss of ABS/stability/traction control indicators, and get the vehicle inspected by a dealer immediately if any appear.
• Owners can file a complaint directly with NHTSA at nhtsa.gov/report-a-safety-problem if they’ve experienced a similar issue — those reports are part of what feeds investigations like this one.
• Keep service records; if a recall follows, documented brake complaints strengthen an owner’s case for repair or reimbursement.

An Engineering Analysis gives NHTSA subpoena-like authority to demand more data from GM and can run for a year or more before a decision. GM has not announced a recall as of this writing. Given the scale — over a million vehicles across two brands — and the nature of the complaint (brake assist failing during active braking, not just after), this is one worth tracking closely rather than shrugging off as routine paperwork.