2024 Cadillac Lyriq

I was driving at a steady 65mph on a highway when the car suddenly surged and the message "1 pedal driving deactivated. Use brakes to stop." I stopped the car with the brakes and restarted it and reactivated 1 pedal driving. Note I was NOT using regenerative braking at the time. The car surged a few miles an hour, and in a heavy traffic scenario could have easily caused a crash.

Since a recent software update, vehicle will unexpectedly give multiple error codes, and disengage “one-pedal driving” mode. This happened recently when coming to a stop at a traffic light behind another vehicle. When coming to a gradual one-pedal stop, the one pedal driving mode unexpectedly disengaged, causing me to almost hit the vehicle in front of me. This error has occurred 5-6 times in the past 3 months.

One pedal driving switched to unavailable while driving - 24 Lyriq AWD I have seen this couple of times while driving now. I keep the one-pedal driving setting on High. I suddenly get an error on Side detection unavailable and One pedal driving turned off - use manual braking. I also feel a slight surge in acceleration while this happens, but I have been able to slow down and re-engage one pedal and it seems to work after that. I am concerned that I may bump into someone in front of me if this happens again, since it has happened a couple of times now!

Hi, this vehicle is owned by Surreal Development LLC. A company whom reverse engineers vehicle. GM has an issue in their Cadillac Lyriq's which causes a complete failure of the vehicle's communication systems without warning while driving. This issue appears to affect all Global B vehicles but it is most severe in vehicles with one pedal driving (Sierra EV, Lyriq, Blazer EV, Optiq, Silverado EV, Equinox EV, etc...) The error is likely within the vehicle's Serial Data Gateway Control Module but it is unclear. The vehicle recovers from the communication quickly (within seconds) but it causes long term adverse affects for that driving period. 1. The vehicle will light up with warnings (Service Traction Control, disengage super cruise, disengage ACC, etc...) 2. The driver's pedal will go into safety mode. 3. A "Service High Voltage" system warning may or may not appear. The safety concern is mostly in #2. When this happens it is very jarring to the driver as it drastically changes how the vehicle responds. While the vehicle may state one pedal driving is disabled many times it still indicates it is on within the controls (likely due to an error in the compounded communication fault). This can lead to the driver rear ending the vehicle in front of them or rolling over. The fault does not correct itself until the vehicle resets (powers off/on). The issue is common and affects many owners of the Cadillac Lyriq. The only diagnostic data we see are communication faults across many modules.

The contact owns a 2024 Cadillac Lyriq. The contact stated that upon engaging the drive mode of the vehicle, the vehicle unintendedly switched back to parking mode. The vehicle was towed to the dealer, where an unknown repair was performed, and the vehicle was repaired. Additionally, the dealer informed the contact that the VIN was included in NHTSA Campaign Number: 25V356000 (Equipment, Electrical System). The contact stated after the dealer performed the recall repair, the vehicle failed to restart. The dealer informed the contact that the manufacturer needed to provide additional remedy to correct the failure. The dealer referred the contact to the manufacturer for assistance. The manufacturer was contacted and referred the contact to the dealer for assistance. The vehicle was not diagnosed or repaired. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was made aware of the failure. The failure mileage was approximately 29,488. Parts distribution disconnect.

While driving my 2024 Cadillac Lyriq in rolling traffic, the vehicle abruptly engaged the brakes without warning or cause. The braking was so forceful I initially thought I had been rear-ended. Once the braking event ended, I began to accelerate—only to discover the vehicle had shifted into reverse without any input from me. This resulted in a rear-end collision. There were no alerts or dashboard warnings to indicate the gear change. I believe this may be related to a malfunction in the automatic emergency braking system or the shift-by-wire controller. This behavior presents a serious safety hazard and must be investigated. I have filed a report with Cadillac and will be taking the vehicle to a dealership for diagnostics and data log review.

This is an update to my original NHTSA complaint submitted on May 5, 2025 (complaint number 11658852), regarding a complete electrical failure in a 2024 Cadillac Lyriq. While parked in a garage, the vehicle experienced a full shutdown—rendering all systems inoperable, including the door locks and windows. Most alarmingly, a [XXX] child was trapped in the back seat due to the doors being electronically locked and unresponsive. The dealership has since diagnosed the failure as a cable routed improperly near the steering column that had rubbed against a component and snapped. This severed connection resulted in the complete loss of vehicle power and emergency functions. Since that time, I have discovered multiple similar reports from other Lyriq owners online describing full system shutdowns, locked doors, and failures to start—many of which are shared on public forums such as Reddit [XXX] ). This suggests that this may not be an isolated case but rather a potential systemic defect in the Lyriq's wiring harness design or electrical architecture. I am extremely concerned that this failure mode could occur while driving, particularly at highway speeds, and would result in loss of steering, braking assist, and emergency exit options. I urge the NHTSA to investigate this issue further to determine whether a recall or manufacturer communication is appropriate. This vehicle is currently with the dealership, and I have refused delivery until GM provides formal safety assurances. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

The main driving display in my 2024 Cadillac Lyriq has faulty software or light sensor calibration - the vehicle automatically dims the screen (including the speedometer) to unreadably low levels, is extremely slow to respond to changing lighting conditions and time of day (the display changes between day and night modes automatically but is constantly confused by lighting conditions). This happens most often at dawn and dusk. I will be driving in bright sunlight with the sun glaring in my eyes, and the screen will think it's night and be dimmed way down to about 20% brightness. Customers have no way of overriding this. There is no setting to disable automatic brightness, and some customers have taken the time to manually unplug the daylight sensor on the dash to resolve their issue. Additionally, the system is extremely sensitive to going under overpasses, which will immediately dim the entire system to about 20% brightness and stay that way for a long time after returning to bright sunlight. This also happens when pulling into my garage, where the display dims down so low that I am unable to see the safety cameras around the vehicle in order to park my vehicle correctly. GM has been made aware of this issue, and they've been aware of it for years. I've spoken to GM directly, and they say, "a fix is coming," but it's been years and nothing has been done. They've issued multiple software updates, none of which address the problem so far. Subsequently released vehicles, like the Optiq, have this issue resolved. GM knows how to fix it, and that's an issue; they just do nothing about it. This is a very well-known, very widespread issue for other Lyriq owners. You can find chat chains on Reddit discussing this issue, and even one where multiple owners talk about starting a class action case on it as it involves vehicle safety. I'm attaching photos of what my display looks like when the sun is out in the morning. It displays the same behavior at dusk.

We were exiting a parking garage when the car suddenly slammed the brakes on in the path of traffic and lost all electrical power. We could not get the car to turn back on or even get it in neutral to move it out of the path of traffic. Our [XXX] old got locked in the car because the car had zero electric power and someone helped us figure out how to unlock the car with the physical key. We were stuck for four hours because no one could figure out how to get the car out of the garage. If this had happened going at a high speed this could have caused a deadly crash, and it happened without any warning. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)