NHTSA Office of Defects Investigation

Engineering Analysis EA26-006: Electronic Brake Module Component Failure

  • Open

NHTSA's Office of Defects Investigation opened Engineering Analysis EA26-006 on August 21, 2026, the day it closed Preliminary Evaluation PE24-011, whose summary cites it; NHTSA's investigations file listed it as open on October 23, 2026. NHTSA's investigations file lists 11 models from 4 makes for it.

Updated daily from NHTSA's investigations file

Key facts

NHTSA number
EA26-006 (also written EA26006)
Investigation type
Engineering Analysis A more detailed stage of a defect investigation, opened when NHTSA's Office of Defects Investigation decides an issue merits further review, often after a Preliminary Evaluation or a Recall Query; it can include vehicle testing, surveys and further information requests.
Status
Open since August 21, 2026
Opened
Vehicle or equipment manufacturer
General Motors, LLC
Component
Service Brakes
Vehicles and equipment
11 models from 4 makes, including the Cadillac Lyriq and Chevrolet Colorado

NHTSA's summary

As NHTSA's Office of Defects Investigation wrote it for Engineering Analysis EA26-006.

On April 11, 2024, the Office of Defects Investigation (ODI) opened Preliminary Evaluation PE24011 after receiving complaints concerning a loss of brake assist in 2023 MY Cadillac Lyriq vehicles. These complaints allege a hard brake pedal, followed by a “Brake System Failure” message at start up or while driving. GM shared records regarding several internal investigations for loss of brake assist due to alleged spindle fractures in the eBoost system. GM has stated that in the event of a spindle fracture, anti-lock brakes (ABS), stability control, and traction control remain functional until the vehicle comes to a complete stop. At this point, ABS, brake assist, stability control, and traction control functions are lost. The loss of these functions causes the vehicle to set one of three Diagnostic Trouble Codes (DTCs) based on failed performance criteria for the Electronic Brake Control Module (EBCM). These DTCs, in turn, activate several driver alerts: an audible chime, a visual “Service Brake System” message in the display, and multiple illuminated Malfunction Indicator Lights (MILs) for the ABS, Traction Control, and Brakes informing the driver of loss of functionality. The vehicle speed will also be limited to 70 KPH (43 MPH). Since opening PE24011, ODI has continued to receive reports of loss of brake assist. Some of these reports describe symptoms inconsistent with GM’s description of a spindle failure. These reports allege an immediate loss of brake assist functionality as opposed to the loss occurring after the vehicle comes to a complete stop. The sudden loss of brake assist during a braking event could result in extended braking distance, which increases the risk of a crash or injury. ODI believes further analysis is necessary to assess the potential for failures in GM’s eBoost system to resulting in safety-related outcomes. At this time, ODI is aware of the following vehicles that are equipped with this eBoost system: 2023-2026 MY Cadillac Lyriq, Chevrolet Colorado, and GMC Canyon; 2024-2026 MY Buick Enclave, Envision; Chevrolet Blazer EV, Equinox EV, Traverse; Cruise Origin; and GMC Acadia; 2025-2026 MY Cadillac Celestiq and Optiq. ODI is also aware of 2024-2026 MY Acura ZDX and 2024-2026 MY Honda Prologue vehicles that were built with this system. The Acura and Honda vehicles were manufactured by GM in a joint venture with Honda, and will be included in the Engineering Analysis as peer vehicles. ODI is opening this Engineering Analysis to further assess the safety-related consequences of a failed eBoost system. In addition, ODI is expanding the scope of the investigation to encompass all GM vehicles that share this eBoost system. To review the ODI reports cited in the Opening Resume ODI Report Identification Number document, go to NHTSA.gov.

Vehicles and equipment listed for this investigation

NHTSA's investigations file lists these vehicles and equipment for Engineering Analysis EA26-006. A listed model year means only that an investigation names it; it says nothing about any particular vehicle. Model years with a try.vin recall page link to that page's NHTSA investigations section.

Buick

All Buick recalls

Cadillac

All Cadillac recalls

Chevrolet

All Chevrolet recalls

GMC

All GMC recalls

What an NHTSA investigation is

NHTSA's Office of Defects Investigation (ODI) looks into possible safety defects in vehicles and equipment, often after owner complaints. An investigation usually starts as a Preliminary Evaluation, or as a Recall Query when it concerns whether an existing recall covers the right vehicles or fixes the problem, and ODI can upgrade it to a more detailed Engineering Analysis. A Defect Petition asks NHTSA to open an investigation, and Audit and Equipment Queries are administrative investigations into whether companies complied with federal vehicle safety requirements, such as reporting, recall and certification rules.

An open investigation is not a finding that a safety defect exists, and NHTSA can close one without a recall.

To see whether a specific vehicle has an open recall, enter its VIN at nhtsa.gov/recalls.

Free VIN check: decode a VIN to see its year, make and model.

Sources

NHTSA's investigation record for EA26-006

Investigation details come from NHTSA's investigations file, which try.vin imports once a day. The investigation types are described from the U.S. Department of Transportation Inspector General's May 2023 report on NHTSA's Office of Defects Investigation, NHTSA's petition rules (49 CFR Parts 552 and 557) and NHTSA's Office of Defects Investigation procedures. How try.vin reads NHTSA investigations.