2024 Cadillac Lyriq

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.

On or about August 6, 2026, I received email communication from the GM EV Concierge , establishing Case #106606137. My vehicle has been "bricked" and GM has had possession of it since August 3, 2026, (46 days and counting) without so much as an official diagnosis or repair timeline. I have repeatedly been told that the matter has been “escalated,” that GM is “working with the dealership,” and that the repair is being “expedited,” however, I don't know to whom it has been escalated, but at this point I have not received any measurable result rather than continuous general status statements. Regardless, the practical result remains undisputed: my vehicle continues to be unavailable, my vehicle has yet to receive an official diagnosis, and I have yet been provided with a reliable repair timeline. GM continues to route my vehicle through a process that has failed to produce an official diagnosis does not resolve the underlying problem. More importantly, it does nothing to address the fact that I remain without the leased vehicle I am paying for while it is under warranty. Because GM continues to possess my vehicle, I have been required to incur over $3,000.00 in transportation and other expenses that I would not otherwise have incurred, not including the sheer amount of time my wife and I have wasted! I specifically request that GM address its own published Trip Interruption Benefits and Assistance provision. GM’s warranty and roadside-assistance states: “Trip Interruption Benefits and Service: If your trip is interrupted due to a warranty failure, incidental expenses may be reimbursed during the Powertrain warranty period. Items considered are hotel, meals, rental car, or a vehicle being delivered back to the customer, up to 500 miles.” I did not ask GM to make an unsupported goodwill payment. I asked GM to determine whether the circumstances I have experienced qualify for consideration under GM’s own published Trip Interruption Benefits and Assistance provision.

NHTSA ID

11764970

Incident

Aug 3, 2026

The vehicle is a Cadillac Lyriq. Following an over the air software update pushed by the manufacturer, the vehicle began displaying a high voltage system error message and lost the ability to DC fast charge. The high voltage components themselves are reported to be functional, the issue appears to be caused entirely by the software update rather than a hardware failure. The vehicle has been at an authorized dealership service center since August 14, 2026, awaiting a resolution. The dealership has confirmed the fault is present and is consistent with a known issue caused by the manufacturer's software update, but has not been able to repair it independently, since the fix requires a corrected software release from the manufacturer. As of this writing, the manufacturer has not issued the corrected update and has not provided a timeline for when one will be available. This creates a safety risk because the vehicle cannot be relied upon for longer trips or situations requiring DC fast charging, which can leave the driver stranded or unable to reach a destination or charging option within a safe range, particularly in hot weather conditions common in this region. The warning message and loss of fast charging capability appeared immediately after the software update was applied, with no prior symptoms. It is unknown whether the manufacturer has independently inspected this specific vehicle beyond the dealership's diagnosis. The high voltage system and charging hardware remain available for inspection upon request. Multiple other owners of this same model have reported the identical issue following the same software update, suggesting this is a widespread defect rather than an isolated incident.

NHTSA ID

11761303

Incident

Aug 14, 2026

On August 9, 2026, at approximately 3:40 a.m., while driving, the vehicle suddenly lost all propulsion and became completely disabled on the roadway. The vehicle remained powered on but would not move forward or backward. At approximately the time of the failure, Cadillac/OnStar Advanced Diagnostics generated a critical Electric Drive Unit warning instructing immediate service and reported diagnostic code P0A78. Additional vehicle diagnostic warnings involved the electric drive unit/high-voltage propulsion system. I immediately contacted roadside assistance but was unable to obtain a workable towing solution for several hours. The vehicle ultimately had to be privately towed and has remained undriveable since the incident. The loss of propulsion occurred unexpectedly while the vehicle was being driven, without advance warning that would have allowed me to safely plan for the vehicle to become disabled. I am concerned that the same sudden loss of propulsion could occur at higher speed, in traffic, at an intersection, or in another location where an unexpected loss of motive power could create a serious crash risk. The vehicle requires diagnosis and repair for the Electric Drive Unit/P0A78 condition.

NHTSA ID

11758673

Incident

Aug 9, 2026

The infotainment screen in my car plus the menu control went completely dead. With the screen dead completely this mean you cannot see the speedomoter, rear camera feeds, warning symbols on the dash. You cannot see current speed, you cannot hear any sound so all alerting systems are down. You are completely blind in a vehicle built around this screen. Dealership has already confirmed faulty computer module. However was told it would have been originally resolved under N252500680. It has only been inspected by the manufacture. No warnings, no nothing, just dead screen out of nowhere that requires new part to bring online. Meaning dead dead; part is currently on back order and design changes were made after this exact model year showing knowledge of the fault.

NHTSA ID

11753137

Incident

Jul 16, 2026

This is about an issue with the ACC system. While driving with the ACC engaged, it will intermittently disengage and without notification. Then the vehicle applies hard braking. After many multiple occurrences, I now tap the brake pedal and apply acceleration. I can't tell you how concerning this can be while driving at interstate speed. Just the thought of a large truck behind me will put the fear into you. Additionally, I have been able to hear an electrical clicking noise emitting from the left side of the steering wheel. When this occurs the ACC is unavailable and/or unable to be selected. A barrage of notifications will appear saying the Adaptive Cruise Control Selected or Cruise Control Selected. Our Lyriq has been in the shop for this problem at least 3 times. Everytime the outcome is CND or WAD

NHTSA ID

11753122

Incident

May 20, 2026

In the past 18 months the vehicle has experienced phantom breaking while driving 3 times. Each time there were no vehicles within 30 or more feet from the vehicle. All 3 times occurred while driving the vehicle and going between 20-40 mph. The vehicle engaged in an emergency break and stopped the car in the road. All three times could have resulted in a major accident as it occurred on busy roadways. This last time it happened in the middle of an intersection with no vehicles around me or behind me. This is a major safety concern and put my family and I in a potentially dangerous situation that could have caused major injuries to myself, my family and others around us. The vehicle is currently with Cadillac being inspected. During conversations with Cadillac they said this is a known issue and suggested that I turn the mechanism off and bypass the safety feature to avoid it from happening again. This is not a systematic fix. This is a bypass. We purchased the car for the safety and security and how sophisticated the safety mechanisms are and we have now been told as a suggestion to simply bypass it. This is very concerning on a national level of That the vehicle is known for doing this. We no longer feel safe in this vehicle The dealer has not confirmed if they have gotten it to duplicate. The only updates we have is that they are still working on the diagnostic testing. There were no warnings prior to the phantom breaking taking place.

NHTSA ID

11749877

Incident

Jul 9, 2026

Component Involved: Steering Wheel Assembly (Super Cruise Steering Wheel Light Bar / Rim)Safety Defect Description:The plastic insert covering the Super Cruise LED light bar and the surrounding leather wrap located directly on the top rim of the steering wheel are breaking apart, peeling, and separating. This is an immediate and severe driving safety hazard. While executing turns and maneuvering the vehicle, the driver’s hands and clothing sleeves are actively getting caught and snagged on the exposed, broken plastic edges and peeling wrap on the wheel rim. This causes physical interference and sudden, unexpected entrapment of the driver's hand or clothing during active steering.Consequences of the Defect:This defect presents an imminent risk of a vehicle crash due to sudden mechanical restriction of the driver's hands. If a driver’s sleeve or fingers become trapped or snagged by the peeling steering wheel trim while negotiating a sharp turn, curve, or emergency evasive maneuver, they will be unable to smoothly rotate the wheel, leading to a direct loss of steering control.

NHTSA ID

11746363

Incident

Jun 25, 2026

I put the car in reverse and released the parking brake. The car started to move backwards. However, the back passenger door was wide open, and the passenger was standing outside the car in the path of the open door. The door hit a guide wire running from the top of a power pole to the sidewalk beside the car. The wire pulled the door backwards, destroying it. This was fortunate. Without the wire in the way, I would’ve had not heard the crashing of the door and would have continued to drive over the person standing beside the car as the passenger door knocked him down. The indicator that the door was still open is so small on the gauge cluster that I couldn’t see that the door was still open when I put the car into reverse. There was no audible warning that I was about to move before all doors were closed, and the emergency braking didn’t stop the car from moving. The passenger’s leg got pushed sideways under the open door. Had the guidewire not pulled the door backwards and caused so much noise that I stopped, the door would’ve broken the passenger’s leg and potentially pushed him under the rear passenger side tire.

NHTSA ID

11739744

Incident

May 23, 2026

If a vehicle has an issue with super cruise inoperative tech is directed to follow a diagnostic path before replacing the Image processing module.

This PI is to instruct dealer on diagnostic procedures that need to be completed prior to replacing a radio or IPC display

This preliminary information advises a dealer on how to email GDS2 session logs into Technical Assistance.

This preliminary information is to inform technicians and customers that GM is aware of the issue and the vehicle can still be driven. When a repair is available, this PI will be updated.

This Preliminary information communicates how to move U018B from Current to History.

This Preliminary information communicates to the technicians a diagnostic tip if a technician loses communication with the image processor #2 and how to restore communication