Home · 2023 Mercedes-benz S-class Phev · Complaints

What 12 owners told NHTSA about the 2023 Mercedes-benz S-class Phev

These are the actual owner complaints behind this car’s reliability verdict, filed with the federal government, unedited. They’re unverified reports, not confirmed defects: read them as leads for your pre-purchase inspection, not a diagnosis.

All (12)Crash / fire / injury (2)Driver assistance (5)Electrical system (3)Tires (3)Body & structure (2)Fuel system (2)Speed control (2)Backup camera & sensors (1)Brakes (1)Wheels (1)

3 of 12 complaints match · Electrical system · clear filters

Dec 17, 2025Electrical systemSpeed controlDriver assistance

While driving on highways using cruise control and adaptive cruise control the vehicle decelerates without driver input. The system also misreads or fails to update speed limit signs causing incorrect cruise speeds and sudden speed changes. This behavior has occurred repeatedly during normal driving conditions and creates a risk of rear end collision from following traffic. The problem has been documented across multiple service visits. A repair attempt was made and I was informed that no repair is currently available. The issue recurred immediately after the repair attempt and remains unresolved. No consistent warning lights are displayed before or during the events. The vehicle is available for inspection upon request.

NHTSA ODI 11705542

Jul 16, 2024Electrical systemBrakesDriver assistance

Emergency stop assist

NHTSA ODI 11602504

Apr 29, 2023Electrical systemBackup camera & sensorsDriver assistance

I leased a 2023 Mercedes from Grapevine Mercedes. When I test drove the vehicle the car had a check engine light on. The sales man said he would get that fixed. The salesman had the service tech clear the code without addressing the issue. A week later the check engine light comes on. The dealership has advised me that the car has a software issue and its unsafe to drive. They must wait for technicians in Germany to fix the problem. It will take weeks. There is a chance the car will shut off while driving.

NHTSA ODI 11519568

Working with the data? Download all 12 complaints as CSV · fetched from NHTSA July 21, 2026

How to use these: a complaint is one owner’s report, filed voluntarily and published unverified. Patterns matter more than any single story. If several owners describe the same failure at similar mileage, put that system at the top of your pre-purchase inspection list. Back to the full 2023 Mercedes-benz S-class Phev verdict →