AI Damage2012 Mercedes-Benz S350: common problems
Owners of the 2012 Mercedes-Benz S350 filed 7 complaints with NHTSA, most often about engine and fuel/propulsion system. Details by component below, with sources.
Key figures
- Owner complaints
- 7
What fails most often
- 1 Engine 43% of all complaints
- 2 Fuel/propulsion system 29% of all complaints
- 3 Powertrain 29% of all complaints
- 4 Vehicle speed control 29% of all complaints
- Engine: 3 complaints (43% of all).
- Fuel/propulsion system: 2 complaints (29% of all).
- Powertrain: 2 complaints (29% of all).
- Vehicle speed control: 2 complaints (29% of all).
Symptoms owners describe
How many of the 7 NHTSA complaints mention each symptom (automatic count from complaint text; one complaint can mention several).
Components owners complain about
| Component | Owner complaints | involving a crash | Technical service bulletins (TSB) |
|---|---|---|---|
| Engine | 3 | 0 | 0 |
| Fuel/propulsion system | 2 | 0 | 0 |
| Powertrain | 2 | 0 | 0 |
| Vehicle speed control | 2 | 0 | 0 |
| Other | 1 | 0 | 0 |
What owners report
Short excerpts of NHTSA complaints in the original wording. These are owner statements not verified by NHTSA; personal data removed.
I did some research on mercedes 3.0l diesel motors and there seems to be an issue with the seal failing about 50,000 miles causing the motor to leak oil and the seal as well as the oil cooler need to be replaced.
"takata recall" the vehicle slips into a limp mode while driving. This have happened several times. I'm taking it to the mb dealer this weekend. 11/16/2016. 57kmiles
Vehicle entered limp home mode while entering intersection. Dealership said codes did not indicate an issue and could not reproduce problem. Only actions taken was a computer test and road test. After leaving the dealer, the vehicle entered the limp home mode again this time on the highway.
While driving at freeway speeds car went into limp mode. Engine rmp were limited to 1500rpm and speed dropped to 25mph.this happened 3 times during week of 3/14/16 and again on 3/22/16. Had to make defensive emergency maneuver to steer the car away from the traffic lanes and stop on the side of the freeway.
The contact then coasted over to the emergency lane and there were no warning lights illuminated. The vehicle restarted; however, the failure recurred multiple times. The vehicle was taken to the dealer for diagnostic testing.
When owners complained
NHTSA complaints by filing year. The peak shows at what age the problems show up most.
Comparison
By complaint count this model year ranks 12,539 of 36,659 model years in the NHTSA data (top 34% most complained about).
On average one model year of the S350 has 4 complaints (4 years in the data). This year has 7, above average.
What to check before buying
- Engine. Cold start, unusual noises, oil leaks and engine codes.
- Fuel/propulsion system. Fuel smell, leaks, rough running, fuel-system codes.
- Powertrain. Shift quality under load, harsh shifts, transmission codes, CV joints.
- Vehicle speed control. Accelerator pedal, cruise control, throttle codes.
Other years of this model
Questions and answers
What are the most common problems with the 2012 Mercedes-Benz S350?
Owner complaints to NHTSA most often mention: engine, fuel/propulsion system, powertrain. Total complaints: 7. The most frequent symptoms in complaint texts: oil leak or consumption (29%), loss of power / limp mode (29%), warning lights, check engine (29%).
How many service bulletins (TSB) were issued for the 2012 Mercedes-Benz S350?
NHTSA lists 0 manufacturer service bulletins for this year. A bulletin tells dealers how to diagnose or fix a known issue; it is not a recall.
Should I buy a 2012 Mercedes-Benz S350 from a US auction?
Owner complaints describe defects, not crash damage. Before bidding, check the components listed above and review the lot photos: VinWind builds a report of visible and hidden damage by VIN.
Other 2012 models
Read also
Sources: public NHTSA data (USA): service bulletins and owner complaints; YouTube: links to videos credited to their authors. Complaints are owner statements not verified by NHTSA, and describe defects rather than crash damage. Data updated 2026-11-06.