The National Highway Traffic Safety Administration has expanded an investigation into an electronic brake system problem affecting more than 1.1 million vehicles from General Motors, Acura and Honda, after reports of lost braking assistance, crashes, injuries and fires. The investigation began as Preliminary Evaluation PE24011 on April 11, 2024, and could eventually lead to a recall.
NHTSA Investigation Covers 1,164,820 Vehicles
According to the National Highway Traffic Safety Administration’s Office of Defects Investigation, an estimated 1,164,820 vehicles from the 2023 to 2026 model years could be affected. The scope includes numerous GM brands as well as the Cruise Origin robotaxi, Acura ZDX and Honda Prologue.
So far, the ODI has received 745 reports related to failure of the electronic brake module component. Those reports include 21 crashes or fires and five injury incidents involving six individual injuries. No fatalities have been reported.
Brake Assist Failures Reported on Multiple GM Models
The issue first appeared in 2023 Cadillac Lyriq EVs, with complaints describing a hard brake pedal followed by a “Brake System Failure” message on the vehicle’s cluster.
GM’s internal investigations found that the loss of brake assist was associated with alleged spindle fractures in the eBoost system. The automaker says anti-lock braking, stability control and traction control continue to operate when the failure occurs, at least until the vehicle comes to a complete stop. The functions are then lost.
The failure can trigger one of three diagnostic trouble codes and activate several driver warnings, including a “Service Brake System” message, multiple malfunction indicator lights and audible chimes. Vehicle speed is also limited to 43 mph.
Vehicles Included in the Investigation
- 2023-2026 Cadillac Lyriq
- 2023-2026 Chevrolet Colorado
- 2023-2026 GMC Canyon
- 2024-2026 Buick Enclave
- 2024-2026 Buick Envision
- 2024-2026 Chevrolet Blazer EV
- 2024-2026 Chevrolet Equinox EV
- 2024-2026 Chevrolet Traverse
- 2024-2026 Cruise Origin
- 2024-2026 GMC Acadia
- 2025-2026 Cadillac Celestiq
- 2025-2026 Cadillac Optiq
- 2024-2026 Acura ZDX
- 2024-2026 Honda Prologue
ODI Reports Raise Additional Concerns
The NHTSA says the ODI has continued receiving reports of lost brake assist since PE24011 was opened in 2024. Some of those reports describe symptoms that do not appear to match a spindle failure.
In some cases, drivers have reported an immediate loss of brake assist rather than losing the function only after the vehicle comes to a stop. The ODI says this could increase crash risk because braking distances increase when brake assist is lost.
As a result, the ODI says additional analysis is necessary and has expanded the investigation to cover all GM vehicles using the eBoost system.
Investigation Could Lead to a Recall
The expanded investigation will take time, and any potential recall would also require time to develop and roll out a fix. The investigation follows multiple serious incidents involving vehicles equipped with the eBoost system.
For now, the NHTSA’s expanded probe places more than 1.1 million vehicles under investigation as officials continue analyzing reports of brake assist failures and determining the scope of the problem.
