Home · 2020 Mercedes-benz S-class Phev · Complaints

What 7 owners told NHTSA about the 2020 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 (7)Speed control (2)Visibility & wipers (2)Electronic Stability Control (esc) (1)Engine (1)Fuel system (1)Steering (1)

Newest first · 7 complaints

Jan 14, 2026

While driving down the road I heard a loud explosion that sounded like a gunshot hit my read window. This caused me to jerk the car and almost hit the driving car next to me. I pulled over and realized that my sunroof had suddenly exploded and shattered onto the shade located in the ceiling.

NHTSA ODI 11710851

Oct 17, 2025Fuel system

The fuel pump My car stopped on the highway [XXX] on [XXX] with my children in the car with no warning at all. I was so lucky nobody hit us and it took 20 minutes of trying to start it to get off of the highway to a gas station where it cut off again The dealer said it is a known problem however my vin number was included despite the fact that they know that the 2020 mercedes benz s450 has an issue that should be recalled due to the severity of the situation and safety of the public. Warning lights did not come on until the car totally stopped. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ODI 11694134

Jul 22, 2024Engine

The contact owns a 2020 Mercedes-Benz S 560. The contact stated while driving 10 MPH, the check engine warning light illuminated. The vehicle was taken to the dealer, where the warning light was cleared; however, the failure recurred the following day. The vehicle was taken back to the dealer, where it was diagnosed that the oil pump and an unknown wiring harness had failed and needed to be replaced. The vehicle was not repaired. The manufacturer was notified of the failure, but no assistance was provided. The failure mileage was approximately 29,100.

NHTSA ODI 11603847

Feb 11, 2024Visibility & wipers

Had windshield breakage and replacement on 14 December 2023. On 29 January 2024, had an apparent windshield strike (pinhead size) and windshield cracked from middle to top. Within 20 minutes crack had spread all across the top of windshield. While parked crack spread down and completely across the bottom of windshield in about 30 minutes. Vehicle is now in Mercedes dealership for windshield service once again. I have been driving for 60+ years and never saw this massive of a windshield crack caused by a pinhead size strike. My belief is that either it was bad glass or installation. I have read numerous complaints regarding Mercedes glass and am concerned whether I can safely operate this vehicle. Would appreciate you looking into this issue.

NHTSA ODI 11571272

Nov 23, 2022Visibility & wipers

The contact owns a 2020 Mercedes-Benz S560. The contact stated that while driving approximately 60 MPH, there was an abnormal sound and shards of glass started entering the vehicle from the sunroof. No injuries were sustained. The vehicle was taken to the dealer; however, the vehicle was not diagnosed. The contact stated that the vehicle was repaired. The manufacturer was notified in writing and he received a call back and was informed that no assistance would be offered. The failure mileage was 38,193.

NHTSA ODI 11494677

May 6, 2020Speed control

INTERMITTENT (AT LEAST A HALF DOZEN TIMES SINCE FEB 2020 PURCHASE) UNINTENDED INCREASE IN SPEED BY AS MUCH AS 35 MPH; TAKEN TO SELLING DEALER WHO COULD NOT DETECT A PROBLEM OR DUPLICATE MALFUNCTION. *TR

NHTSA ODI 11323574

Dec 12, 2019SteeringSpeed controlElectronic Stability Control (esc)

AUTOMATIC DRIVE SHUTS OFF WHEN YOU BRAKE. HOWEVER, IN A ROLLING STOP AND BRAKE, IT DOES NOT RESTART IN CERTAIN SITUATIONS WHEN YOU ACCELERATE OUT OF THE STOP. IT IS INCONSISTENT, BUT SERVICE TEAM AT LOCAL DEALER HAVE RECREATED THE SITUATION. THE CAR IS DESIGNED TO AUTO RESTART AND THE FUNCTION CANNOT BE DISABLED.

NHTSA ODI 11288650

Working with the data? Download all 7 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 2020 Mercedes-benz S-class Phev verdict →