Home · 2011 Mercedes-benz C-class Phev · Complaints

What 516 owners told NHTSA about the 2011 Mercedes-benz C-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 (516)Crash / fire / injury (25)Airbags (269)Suspension (62)Fuel system (51)Body & structure (50)Electrical system (46)Steering (35)Lights (21)Brakes (13)Engine (11)Transmission & drivetrain (10)

Newest first · 516 complaints · page 2 of 21

Apr 30, 2024Body & structure

So i was using my car daily for go to work and I was on the highway and they happened a accident in front of me so I have to slow down due to the accident i was going 70 miles per hour and when made a hard break my car turn sideways due to the rear subframe was broke and I dint even notice that the part was rotten they i start looking online and I noticed that the majority of those car come with that factory issue.

NHTSA ODI 11586041

Apr 12, 2024AirbagsCrash1 injury

I was in a collision and the airbags did not deploy. There was a recall on airbags for the Mercedes C300 within the year my vehicle was made, however, the recall did not include my VIN. Also, the sunroof drain is faulty, which was also recalled on other Mercedes C300s within the same production year, again not my VIN, but upon inspection by a certified dealership, it appears to be the same issue as other recalled vehicles.

NHTSA ODI 11582626

Apr 9, 2024Suspension

Recently I was driving and heard a knocking/creaking noise in the left rear. When braking I felt as though I was going to lose control of the vehicle...vehicle appeared to fishtail and pull to the left. I first noticed it on [XXX] when I was driving on the highway in excess of 60 MPH. On [XXX] I brought it to my mechanic (Genesee Auto Repair, 40 Liberty Street, Salem, NH (603)898-1899) and my mechanic informed me that the left rear subframe had rotted out and told me that I should not be driving the car. There were no warning lamps or messages indicating there was a problem. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ODI 11581865

Apr 2, 2024Electrical systemLights

The right rear tail light housing harness melted due to an electrical issue. Wire tends to heat up too much. This caused my right rear tail light, right break light and right side turn signal not to function.

NHTSA ODI 11580578

Mar 13, 2024Electrical system

The contact owns a 2011 Mercedes-Benz C300. The contact stated that when starting the vehicle, the ignition was not reading the key, and the steering wheel was locked. The message to remove the key from the ignition was displayed. Additionally, the fuel gauge was inoperable and not reading the fuel level. The vehicle was taken to the dealer where it was diagnosed with a locked steering wheel and the steering wheel lock needed to be replaced. The vehicle was not repaired. The contact was informed that the parts were ordered to complete the repair. The manufacturer was not made aware of the failure. The failure mileage was approximately 100,100.

NHTSA ODI 11577103

Feb 27, 2024Lights

We had notifications on our dashboard that rear driver side (left) lights were out while driving car. We thought the light bulbs just had to be replaced. We brought to mechanic to just fix lights & they discovered the light ground wire burned out & caused light holder to be damaged as well where ground wire was. It caused rear driver side tail lights to fail. We had light bulb holder with wires all replaced on 2/23/24. This issue was a recall back in 2014 & seems to be a reoccurring issue with this part of the Mercedez 2011 C class.

NHTSA ODI 11574237

Feb 21, 2024Electrical systemAirbags

The sam box (electrical system fuze panel) located under the hood is in a spot where if the lid isn't on correctly water will drain from the windshield right into the sam box and cause the vehicles electrical system to deploy the steering wheel airbag. That's at least what happened to me. It was raining out that day and I guess I went over a bump that caused the lid of the sam to get out of place. I drove home and the car seat for a few hours. I went out upon unlocking the door as soon as I pulled the handle to open the driver side door the steering wheel airbag blew and the vehicle is now in srs mode. The dealership had told me that it's a design flaw but wants me to pay for the diagnostic. No lights were on and I did not file a police report.

NHTSA ODI 11573072

Feb 13, 2024SteeringSuspensionBody & structure

Non operating. No tags . No plates.

NHTSA ODI 11571578

Jan 16, 2024Electrical system

Melted taillight socket board.

NHTSA ODI 11565848

Dec 21, 2023AirbagsCrash1 injury

The airbags were supposed to have been fixed per recall by carriage house Mercedes in new London ct. my son was in a horrible front in collision and they did not deploy. None of them did. Accident happened 3 days ago insurance will pick up car today. I’d like this noted incase they need evidence

NHTSA ODI 11561237

Nov 8, 2023

the rear subframe on my car rotted out. Before they called a recall/extended warranty,I paid to have it fixed. Since it is a 2011, I was not about to pay $7,000-$9,000 to get a new one. I made the best decision with the information I had at the time. It broke in June of 2022. I had the car fixed with a used subframe from Atlantic Auto. Once I realized there was FINALLY a recall/Extended warranty, I submitted All necessary paperwork and have been denied. I wrote to Mercedes Benz Corporate office. They contacted the Warwick store. Went back and forth All summer and they have refused to reimburse me the &2,299. that I spent to fix the car. It says the decision is made on a case by case review. They have denied my claim. I have all the correspondence between myself and Mercedes Benz.

NHTSA ODI 11554128

Nov 3, 2023SuspensionBody & structure3 injuries

The subframe has rusted/fallen off. This is incredibly risky as the car cannot be driven safely and it happened without warning. My mechanic said it is not due to any driving incidents but through rust occurring on Mercedes' subframes, which are flimsy. It has been inspected professionally by a mechanic. There are NO warning lamps. This could kill someone on the highway as while braking the car veered left and right. I had small children in the car we all neck pain from the car veering while stopping on the highway. I have taken good care of my vehicle and have all maintenance current. This is a fault with the material on the subframe. For MB: All the subframes are on backorder and are incredibly expensive to fix. I have a video of the damage from the mechanic if needed.

NHTSA ODI 11553395

Oct 30, 2023Fuel system

The contact owns a 2011 Mercedes-Benz C300. The contact stated after adding more than 3 gallons of fuel to the vehicle, there was a strong fuel odor inside the cabin of the vehicle. The contact stated that the failure had been recurring and was making him unwell. The vehicle was taken to the dealer, where it was diagnosed and determined that the failure was related to NHTSA Campaign Number: 12V557000 (Fuel System, Gasoline). The vehicle was not repaired. The manufacturer was notified of the failure and referred the contact to the NHTSA Hotline for assistance. The failure mileage was unknown.

NHTSA ODI 11552746

Sep 7, 2023Fuel system

On 8/3/2023 we could smell a strong gasoline smell inside and outside our 2011 Mercedes C300. We towed the car to a Mercedes specialty repair shop for inspection. The found that the passenger side fuel pump cover (which is a large cylinder assembly actually) was leaking due to cracked plastic. Gas vapors could be detected outside the car, in the trunk, and in the car as the gas tank is right under the back seat. Our mechanic said he had just fixed another Mercedes with the exact same problem. Apparently this is a well known defect and I understand that Mercedes has an extended warranty for later models. We believe the extended warranty should be extended to our 2011 C300 which has only 55,000 miles.

NHTSA ODI 11543139

Aug 28, 2023

Over the weekend my vehicle driver side interior door handle became inoperable not allowing me to open my door from the inside. The handle flaps back & forth with no connect to the inside of door panel not making be able to get out of my vehicle. I was stuck & had to climb over to passenger side to get out. It only opens from outside . It has been functioning well for the life of me owning the vehicle, never giving me any problem until now, suddenly with no warning that it was breaking. My Mercedes dealer said I need a whole door panel & they have had several calls from other C300 owners where this handle broke also recently. So they are aware & admitted so. This is a recall or factory defect in my eyes. Also I looked online & this is very common because of a plastic not metal part Mercedes uses . Is this not unsafe enough to be recalled? It’s a no brainer! Not bein able to exit your vehicle at all. I was so scared and shocked a car of this class has this safety issue and they do not do a thing to their owners to fix it, its on owner and their pockets. This should be taken care of immediately for free. Are they waiting for someone to have an accident and lose their life to act on replacing this problem?! Again I feel this is a major safety recall that needs to be addressed ASAP. Safety, peace of mind, accessibility to exit/enter your vehicle. If no one can help you from the outside, you have to climb out from passenger side or thru the back of the vehicle. You can open your window too, but what if that jams electrically ….you are stuck. $900 plus labor should not be on me but should be in Mercedes hands to value my life & others lives more than any price as a standard part of their fleet of cars they have driving across USA. High end luxury car w/a faulty door handle that leaves you unable to get out, unbelievable ! Has safety hazard written all over it. I have a video & submitted a pic of my issue. This is my second MB I owned and I never had this danger occur.

NHTSA ODI 11541196

Aug 22, 2023SuspensionBody & structure

2011 C300 4matic Sport I'm very concerned about the front subframe after going over the invoice and everything that was replaced on the rear subframe due to a recall Mercedes issued. But wait doesn't the whole subframe have severe rust corrosion all throughout yes it does per mechanic/technician. I'm having steering issues while driving the vehicle when applying the breaks the vehicle pulls very hard to the left the whole car swerves to the left very dangerously. After getting it checked out the mechanic/ technician pointed out that the control arm snapped from the Front subframe due to severe corrosion. I'm not understanding how the recall was only for the rear subframe only. The whole entire subframe is severely rusted. Front subframe which may experience premature wear of the front axel carrier and a fracture risk, potentially resulting in sudden loss of steering control. After internal endurance testing determined the front axle carrier supplied for certain Mercedes SUV’s and cars may weaken prematurely. An investigation revealed the root cause of the problem was due to a manufacturing defect in which the parts did not receive proper corrosion protection. My front subframe did not receive the proper corrosion protection. It's available for inspection. It's currently still at the dealership due to being unsafe to drive. I'm having steering issues while driving the vehicle when applying the breaks the vehicle pulls very hard to the left the whole car swerves to the left very dangerously. The problem has been reproduced or confirmed by a dealer or independent service center. The vehicle or component has Not been inspected by the manufacturer, police, insurance representatives. Only Dealer and independent service center did the inspection. No warning indicators no other symptoms, this issue took place around February - March of 2023. When I received the letter about the subframe recall I was excited thinking the issue would be fixed. But No it's unsafe

NHTSA ODI 11539978

Jul 21, 2023Fuel system

Each time I filled my gas tank, there was an overpowering odor of gasoline inside the car and outside on the passenger side. Once the tank would get down below 3/4 of a tank, the odor would dissipate until down to a 1/4 of a tank it would go away completely.

NHTSA ODI 11533725

Jul 21, 2023Fuel system

I suspect a failure in the fuel tank / system seal, which is allowing gas fumes into the cabin. There is a strong smell of gasoline inside the cabin especially after a full tank refill. This issue was also a problem for my 2008 Mercedes Benz E350. It has not been inspected but since my E350 had a similar extended warranty repair, I assume this would be similar. The strong fumes and odor in the cabin is a health risk of breathing the fumes or explosion. There are no warning lamp to indicate this failure. No recalls or extended warranty currently to fix this problem.

NHTSA ODI 11533736

Jul 21, 2023EngineFuel system

There is a crack in the flange causing a fuel leak in my C300 2011 Mercedes-Benz built March 2011. A strong gas smell fills the car. This situation is extremely dangerous and should be included in the recall that was approved for vehicles C300 manufactured from April 2011-July 2011. Please include my vehicle in this recall. There is only a one month difference.

NHTSA ODI 11533738

Jun 21, 2023Fuel system

My check engine light came on approximately one month ago. Once tested it indicated a fuel vapor leak. I pulled out of a driveway and a large stream of fuel spilled all over the roadway. Approximately 7 feet in length about 5 inches in width was on the road. I took it to a Mercedes repair shop and they informed me I had a fuel leak and that it was not safe to drive. There was corrosion and rust forming on the tank which seems very odd since the car is garage kept and we don't get much snow in Kentucky. My daughter rides in this car with me and they told me it is very dangerous and needs repaired. If I was to drive over a cigarette we could essentially blow up. I had a second shop look at it and they also informed me I had a fuel leak and would need to replace the fuel tank. I was told there was a recall on some models of Mercedes for this issue but can't seem to find one on my year make and model. Please help with this matter so my daughter and I can remain safe as well as others around us. Seems like we are in a ticking time bomb.

NHTSA ODI 11528210

May 15, 2023EngineFire

The contact owns a 2011 Mercedes C300. The contact stated that while driving approximately 15 MPH the check engine began flashing and the vehicle stalled. The contact attempted to restart the vehicle and smoke was observed emanating from the front driver's tire. The contact stated that the fire exploded from the engine compartment. Additionally, the contact stated that she was locked in the vehicle by the driver's seatbelt, but was able to get out of the vehicle. The fire department extinguished the fire and a report was taken. There were no injuries sustained. The vehicle was towed to a salvage lot. The contact was not sure if the vehicle restarted. The manufacturer was not notified of the failure. The failure mileage was approximately 120,000.

NHTSA ODI 11522090

Apr 14, 2023Body & structure

Good morning. I previously reported incident [XXX] about a subframe issue w/ my 2011 Mercedes Benz C-300. This morning I received a warranty extension from the originally expired 4 years/50,000 mile to 20 years/unlimited miles. The notice says that repairs must be performed by an authorized Mercedes Benz dealership. I had the auto fixed privately and filed the NHTSA request. I called their CS and was told that I would need to visit a dealership, but to be honest I think that would be fruitless. Can MB be compelled to reimburse me for the cost incurred? Regards, [XXX] INFORMATION Redacted PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6).

NHTSA ODI 11517021

Apr 14, 2023SuspensionBody & structure

Like apparently the majority of this model year C300, the rear subframe is completely disintegrated. This is a known issue but Mercedes has not communicated it nor fixed it. I was told, and as the photos clearly indicate, this very likely could have resulted in a catastrophic or fatal accident as the entire rear is corroded. I have photo and video support as well as the inspection from a mechanic.

NHTSA ODI 11517129

Mar 28, 2023Body & structureVisibility & wipers

The contact owned a 2011 Mercedes-Benz C300. The contact stated that upon entering the vehicle, he noticed that the inside of the vehicle was flooded with water. The contact then stated that he noticed that water had leaked from the sunroof and entered the cabin of the vehicle. The contact stated that several unknown warning lights were intermittently illuminated. The vehicle was taken to an independent mechanic where it was diagnosed that the wiring harness was severely damaged and could not be repaired. The dealer was not notified of the failure. The vehicle was not repaired. The vehicle was deemed a total loss by the insurance company. The manufacturer was notified of the failure and the contact was provided a case number. The failure mileage was 82,242.

NHTSA ODI 11514167

Mar 27, 2023SteeringSuspensionElectrical system

Car slow down and stop and cannot start in traffic….

NHTSA ODI 11514093

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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 2011 Mercedes-benz C-class Phev verdict →