Home · 2021 Mercedes-benz S-class Phev · Complaints

What 33 owners told NHTSA about the 2021 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 (33)Crash / fire / injury (4)Electrical system (10)Wheels (6)Driver assistance (5)Engine & cooling (5)Brakes (3)Engine (3)Lane Departure (3)Speed control (3)Communication (2)Fuel system (2)

5 of 33 complaints match · Engine & cooling · clear filters

Dec 20, 2024Engine & cooling

The contact owns a 2021 Mercedes-Benz S580. The contact received notification of NHTSA Campaign Number: 24V704000 (ENGINE AND ENGINE COOLING); however, the part to do the recall repair was unavailable. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was made aware of the issue. The contact had not experienced a failure. VIN tool confirms parts not available.

NHTSA ODI 11631798

Dec 4, 2024Engine & cooling

The contact owns a 2021 Mercedes-Benz. The contact stated while driving at 10 MPH, the vehicle stalls until the contact engages the vehicle in sport mode. The vehicle was not taken to an independent mechanic or dealer for diagnosis or repairs. The manufacturer was not notified of the failure and a case was opened. The contact was relating the failure to  NHTSA Campaign Number: 24V704000 (ENGINE AND ENGINE COOLING). The failure mileage was 20,700.

NHTSA ODI 11628889

Nov 15, 2024Engine & cooling

The contact owns a 2021 Mercedes-Benz S 580. The contact received notification of NHTSA Campaign Number: 24V704000(Engine and Engine Cooling); however, the part to do the recall repair was not yet available. The contact stated that while starting the vehicle, the engine made an abnormal ticking sound. There was no warning light illuminated. The local dealer was contacted. 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 not made aware of the failure. The failure mileage was approximately 38,000. VIN tool confirms parts not available.

NHTSA ODI 11625473

Jan 5, 2022Engine & coolingElectrical system

The contact owns a 2021 Mercedes-Benz S580. The contact stated that while driving, the navigation system became inoperable. There were several unknown warning lights illuminated. The contact received notification of NHTSA Campaign Number: 21V843000 (Engine and Engine Cooling) however, the part to do the recall was unavailable. The vehicle was taken to the local dealer however, the mechanic was unable to duplicate the failure. The contact stated that the manufacturer exceeded a reasonable amount of time for the recall repair. The manufacturer was notified of the failure however, no further assistance was provided. VIN tool confirms parts are not available. The approximate failure mileage was 600.

NHTSA ODI 11446332

Dec 13, 2021Engine & cooling

The contact owns a 2021 Mercedes-Benz S580. The contact received a notification for NHTSA Campaign Number: 21V843000 (Engine and Engine Cooling) however, the part to do the recall repair was unavailable. The dealer had been notified about the recall; however, the contact was informed that the parts were not yet available. The manufacturer had also been notified of the recall but offered no assistance. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The contact had not experienced a failure. VIN tool confirms parts not available.

NHTSA ODI 11443625

Working with the data? Download all 33 complaints as CSV · fetched from NHTSA July 20, 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 2021 Mercedes-benz S-class Phev verdict →