2015 Mercedes-Benz C-Class
Problems, recalls and owner-reported issues
Engine is the leading concern among 449 owner complaints filed for this model year. This is the 7th highest complaint count among 23 C-Class model years with reports.
Of the 2015 reports, 11 involved a crash and 1 involved a fire. 10 people were injured.
What owners report most often
Recalls and investigations
No safety recalls on file.
Representative owner complaints
449 reports, newest first.
Fuel/propulsion system, Mar 1, 2022
When I got my Mercedes 2.5 years ago I would always notice a very strong gas smell that would come very randomly. I would have to open my windows for the smell of fuel to go away. I presented this to the Greenway Mercedes Dealership 2X VERBALLY and they told me that it is just a "Mercedes thing" and everything is ok because it is not "VISIBILLY" leaking fuel. Which it was not. However, the smell of the fuel is EXTREME, It would happen to me through out the year (in the summer and winter, regardless of temperature) randomlly. I would have to leave the garage ASAP when I turn on my car just in case the smell of fuel was extreme because my parents would tell me that it would even COME INTO THE HOUSE. I thought I was crazy to think this was normal and just a "Mercedes thing". But then I got a letter on August 2021 and did some research and saw I was not the only one and there is a class action lawsuit -Mercedes sent a letter on August 21 announcing they will extended the limited warranty of the "Fuel hose connected to high pressure fuel pump" from the original warranty of 4 years/50,000 miles to 10 years/120,000 miles. HOWEVER, This does NOT HELP, they are still saying it is a wear and tear and REFUSE to replace the defected MANUFACTORER part and INSIST it is not "seeping fuel" from the connection at the fuel pump, so it is NOT under warranty. I am confused as to why this is not a recall? Extending the warranty did nothing to help Mercedes Owners at all. They continued to claim it is "wear and tear so that is why the fuel is sweeping at a different location" AS WELL, two dealerships told me it would take them 24-48 hours for them to JUST INSPECT my car to see if it is covered. This extension did resolve anything, but made sure the dealerships deny even more. Now, I have to continue to leave my garage within 30 sec. so I don't suffocate the cats that sleep in the garage or have my family smell the fuel as I leave. And to open my windows so I can breath fresh air.
Engine, Fuel/propulsion system, Feb 4, 2022
Car has 51,000 miles , no check engine light or any other warning light .driving in on the freeway at 70 mph when I hear a pop sound and my car loses power , I pushed on the gas and it started to shake violently and I panicked as the construction on the freeway was not allowing drivers a shoulder to pull over on . I was lucky enough to be driving at 2am and with the construction going on , drivers were already slowing down . My car also started blowing a thick white smoke through the back exhaust that could have made it harder to see that late night as it was already foggy here in California . At first I didn’t realize I was smoking through the back until my car began smelling like burnt oil . I wasn’t able to get off the freeway until the next exit all while thinking that my car was going to explode from the smell of the burning oil . When I pulled over and got out of the car I made sure I didn’t see any fire and then I waited to let it cool down , opened the hood and saw oil everywhere . I had it towed to Mercedes and I got the problem and the estimated cost to repair it . The problem turned out being a cracked piston in cylinder one , when it cracked it allowed oil to mix with the gasoline and that’s what was causing all the white smoke out the rear , the burnt smell was from the oil that was leaked all over my engine getting too hot from the engine. I found out a few days ago that Mercedes’ has a technical billeting regarding a faulty wrist pin that was causing the pistons to eventually crack . In the bulletin the faulty pin problem is fixed by replacing all the pistons and adding a upgraded pin and many other parts . So there are many other drivers that are experiencing this and driving with faulty wrist pins . Prior to all this happening the car always made a tap tap tap sound from engine and Mercedes’ said it was normal for 4cylinder turbos to make this sound, sounded like a diesel . But it turned out being from the loose wrist pin . Mercedes lied to us . THE CONSUMER REQUESTED THAT MERCEDES BENZ VEHICLES, WITH THE M274 ENGINE, BE INVESTIGATED. THE CONSUMER STATED THE VEHICLE SUDDENLY LOST POWER. THE CONSUMER STATED THE CAUSE MAY BE DUE TO A WRIST PIN THAT IS THE WRONG SIZE.
Engine, Jan 21, 2022
The wrist pin is defective in early engines during manufacturing. It is not safe to operate the vehicle because at any time without any warning this can cause fatal damage to the engine - piston crack resulting in total loss of control even at high speeds on the highway. Numerous complaints were filed on NHTSA regarding cracked pistons most likely related to this wrist pin manufacture defect. The problem is acknowledged by M-BENZ (NHTSA ID Number: 10058545), and starting around April 20 2015 M-BENZ started to install modified wrist pins to prevent future failures, but they did not address existing faulty wrist pins. The vehicle was always serviced at the official MBENZ Dealer service and was under comprehensive inspection multiple times but the issue was never acknowledged by the service technicians during the warranty period even though the issue existed since manufacturing and instruction of how to diagnose was distributed between service technicians via Manufacturer Communication Number: LI03-10P060916 in 2015. When the M-BENZ Delear service technician finally confirmed the issue, the vehicle was already out of warranty and there is a hefty price to a customer to fix this manufacturer defect that should not have been there in the first place. There are no warning lamps, messages, or other easily detectable symptoms of the problem prior to the failure. The issue can be diagnosed under very special conditions described in Manufacturer Communication Number: LI03-10P060916 For most drivers, it's hard to diagnose that something is wrong and easily mistaken for normal operation noise of the engine
Engine, Jan 21, 2022
The contact owned a 2015 Mercedes-Benz C300. The contact stated that while idle, the engine would vibrate with an abnormal sputtering sound coming from the engine. As the failure persisted, the check engine warning light illuminated. The contact had initially taken the vehicle to a dealer and the spark plugs were replaced; however, the failure persisted. The vehicle was returned to the dealer and a diagnostic test was performed, and it was discovered that an engine cylinder had blown. The vehicle was diagnosed with engine failure and the contact was provided an estimate for the repair. The contact then spoke to an independent mechanic who informed her that the failure was a common failure for her model vehicle. The manufacturer was also notified of the failure and a case was filed. An email was sent to the manufacturer and the contact was informed that no further assistance could be offered. The vehicle was not repaired. The failure mileage was approximately 50,900.
Structure, Other or unspecified, Jan 10, 2022
Recall 2021070010----NHTSA #21V197--Panoramic roof not boned correctly to the vehicle during prior replacement -
Other or unspecified, Jan 7, 2022
The car have anew recall Recall #2021070010. The dealership Garage Isla Verde won’t provide me any type of services to my car. Neither repair this safety recall. They cancelled my appointments because I’m not welcome to the dealership.
Engine, Jan 6, 2022
Without any warring or indication my engine would start making bad noise then light comes on to check engine as the motor fails and car shuts off. This is while driving and has happened two times now. Both times I find it’s due to spark plug failure and pieces of the plug go throughout the engine and severely damage. First time this happened at 82,000 miles and was covered by warranty. Now this has happened again on the new engine with 81000 miles on it. I seen many forums on this issue. This time it’s not under warranty and it’s $18000 to fix. Mercedes Benz w205 engine seems to be notorious for spark plug failure in cylinder 1 as well as piston cracking. The first time this happened was October 12th 2019 and the warranty work was done at fletcher Jones Mercedes Benz of Newport Beach
Steering, Jan 6, 2022
Power steering malfunctioned while driving. Received error on dash. The steering wheel was very difficult to turn. Issue was resolved after turning the car off for 5mins and restarting. However it is unclear whether the issue would fester again. This is the first time this issue occurred between 2017-2022.
Fuel system, Gasoline, Dec 20, 2021
The contact owns a 2015 Mercedes-Benz C300. The contact stated that a strong fuel odor could be smelled from both inside and outside the vehicle. The vehicle had to be serviced for the failure; however, upon inspection, the contact believed that the source of the odor was from the engine fuel lines. The dealer was notified of the failure and informed him that there were no recalls on the vehicle. The manufacturer had yet to be notified of the failure. The vehicle had yet to be repaired. The failure mileage was approximately 102,000.
Fuel/propulsion system, Dec 19, 2021
Constant fuel smell coming from the engine, you can see gas coming out of the high pressure line. When I park in the garage the whole house smells like gas. Even while driving gas smell coming through the vents constantly
Engine, Dec 17, 2021, fire
The contact owns a 2015 Mercedes-Benz C300. The contact stated that while driving approximately 50-60 MPH, the #1 piston cracked. The contact stated that while his daughter was driving, the vehicle was shaking and smoking. The check engine warning light illuminated. The vehicle was towed to an independent mechanic and the contact was informed that the #1 piston was cracked, engine cooler, P0301 cylinder #1, P219 solenoid failure. The vehicle was taken to another independent mechanic and the engine was replaced. The contact called the local dealer, but the vehicle was not diagnosed or repaired. The manufacturer was notified of the failure, but no further assistance was provided. The failure mileage was approximately 105,102.
Other or unspecified, Nov 30, 2021
on 7/17/21 the piece of the top of the car right from the from window leading to sunroof came undone and flew off while on highway. vehicle was repaired a month later at body shop. this was out of pocket due to not wanting to claim on my insurance due to deductible. This piece flew off at a high velocity with no warning and couldve caused a accident. There was no indication of any issues no lights no warnings signs. There was a loud noise like a brick or large object falling on top which then I heard a lot of air. Recently again in October 5 I was driving on the highway and debris hit my sun roof, my window was shaking and I went to the body shop. in the brief drive there some 10 miles the same plastic part repaired was lifted and coming off. on this occasion I used my Insurance. On 03/2/22, another event in which the plastic portion between front window and rooftop flew off while driving 60mph on the highway.
Structure, Oct 31, 2021
Panoramic sunroof off centered causing glass to tilt on one side above vehicle. Note, a recall for the same on models 2015 c300 for vehicles with prior service but same issues/ problems for my vehicle that has not been serviced.
Engine, Oct 14, 2021
Check engine light came on. Code P052E. Had this code in 2018 and the pcv valve and line were changed. Currently has the same issue 3 years later. This is a very common problem with mercedes that have this engine.
Air bags, Oct 8, 2021, crash
The contact owns a 2015 Mercedes Benz C250. The contact had initially received a recall notice for NHTSA Campaign Number: 19V010000 (AIRBAGS). The contact took the vehicle to the local dealer and had the recall serviced. The contact stated that while driving at 35 MPH, another vehicle made a left turn and hit his vehicle in the middle of an intersection. The contact stated that the air bags did not deploy upon impact. The authorities were called to the scene and a police report was filed. No medical attention was rendered at the scene of the accident. The vehicle was towed to an independent mechanic where it remained in their possession. The contact sought medical attention later that day at a local hospital where he was treated for a strain to his left neck and left leg. The dealer nor the manufacturer had yet to be notified of the failure. The vehicle had yet to be repaired. The failure mileage was approximately 60,000.
Fuel/propulsion system, Oct 1, 2021
Hi so i woke up this morning and my started my car as usual then noticed the smell of gas all around the car Inside and out. I got worried turned off the car and started sniffing around to see if i can find where the leak was and found out the high pressure fuel pump was leaking i looked up info on this part and it is very common on these car for that part to fail. Im very upset that there is no recall yet when the dealership told me that they do 2-3 of those jobs a week (HIGH PRESSURE FUEL PUMP REPAIRS) and still no recalls on this,what is it going to take to get one?, my car has to blow up to get your guys attention?? Oh wait other Mercedes c300 cars in the united states already caught on fire please fix this saftey hazard i want to feel safe and not worry about catching on fire. ITS BEEN 6 years AND STILL HAVE NO RECALLS FOR THIS CAR ???
Engine, Sep 30, 2021
The engine stalled at idle numerous times when at a stop light or stop sign. This was dangerous as the other cars could have ran into my car in anticipation that I should be moving with traffic. The car was taken to the Mercedes Marin dealer service center and diagnostic was done indicating a cracked piston in cylinder one was causing loss of compression and could also cause engine failure at speed if not taken care of. Check engine light DID NOT come on. During research on repairs for this issue, it became apparent that Mercedes Benz is aware of this issue in many of its engines of this model and year, but did nothing to remedy the situation or the underlying manufacturing defect that causes the cracked piston. In addition, Mercedes is unwilling to cover the cost of repair or replacement (car has only. 49,000 miles, but is out of warranty due to age).
Structure, Sep 16, 2021
The contact owns a 2015 Mercedes-Benz C300. The contact stated while driving 50 MPH, the contact heard an abnormal flapping sound coming from the opened panoramic moon roof. The contact reached up into the open moon roof and discovered that the adhesive bonding on the front panel had started to deteriorate. The contact took the vehicle to the local dealer and was confirmed the failure however, the contact was informed that the dealer was not equipped to perform the repair. The contact was referred to Mercedes-Benz of Wilkes-Barre (150 Motorworld Dr, Wilkes-Barre, PA 18702) where the mechanic removed the bonded panel and installed a new front panel which the contact paid for out of pocket. The first dealer then notified the contact of NHTSA Campaign Number: 21V197000 (Structure) and instructed him to call the dealer where the vehicle was repaired. The second dealer was notified of the failure and informed him to call the manufacturer for potential reimbursement. The manufacturer was notified of the failure and informed him that the vehicle was not included in the recall. The vehicle was repaired. The failure mileage was approximately 68,000.
Structure, Sep 4, 2021
Panoramic glaaa sunroof mounting bracket made of cheap thin plastic that it breaks easily allowing the panoramic glass roof to fly off the car if driven while open.
Structure, Aug 3, 2021
The contact owns a 2015 Mercedes-Benz C300. The contact’s wife stated while driving 70 mph, the roof panel separated and detached from the vehicle. The vehicle was diagnosed but not repaired. Upon investigation, the contact associated the failure with NHTSA campaign number: 21V197000 (Structure) however, the part to do the recall repair was not yet available. The manufacturer was informed of the failure but offered no assistance. The failure mileage was approximately 57,000.
Seat belts, Jul 15, 2021
I would like to bring to your attention a potentially dangerous design flaw in my 2015 Mercedes C300. That design flaw resulted in me having to cut the seat belt off a passenger, my wife, in order to free her from the car. I will also explain in detail the admittedly rare circumstances that led to this potentially dangerous incident. In May 2021, my wife underwent outpatient surgery of her left shoulder. After the surgery a nurse brought my wife to the curb in front of the hospital, where I had pulled up my car. The nurse and I assisted my wife with her transfer from the wheel chair into the passenger seat. My wife was wearing a sling supported by a spacing pillow on her left arm. The nurse then proceeded to fasten the seat belt around my wife. Since the nurse’s procedure is of importance to this incident, I will explain it in detail. After my wife was seated, the nurse unwound the passenger seat belt entirely and inserted the belt tongue into the buckle so that the lap part of the seat belt went properly around my wife’s lap. To protect the fresh surgical site from external forces, the nurse then placed the part of the seat belt that is normally worn across the chest BEHIND my wife’s back. Had the seat belt been placed properly across my wife’s chest, it would have been forced to pass over her left arm, which was tied to her body by the sling and bandages. It was thus not possible to wear the chest part of the seat belt properly over the chest but under the left arm. Lastly, the nurse allowed the fully extended seat belt to wind up onto the pretensioner. Upon arrival at home I wanted to take the seat belt off my wife. To this end I opened the passenger door, and gently pulled on the seat belt in order to slacken it enough to get the seat belt off her. However, I could not get any slack. Per instructions in the user manual, I opened the belt buckle but the belt was tightly wound around my wife's body. Ultimately, I had to cut the belt with scissors.
Structure, Jul 15, 2021
Panoramic Sunroof has had several problems previously. While driving 65 mph the plastic roof piece between the windshield and sunroof suddenly and unexpectedly dislodged and flew off the car.
Other or unspecified, Jul 12, 2021
The panoramic sunroof of the C300 is held in plastic hooks that break, even with normal use. So, that leaves the panoramic roof to fly off the vehicle on the highway. I have not opened my roof in three years because I am afraid it might not hold up. Looking at the MB owners' forum, it seems to be a pretty common issue that these plastic hooks break, and then the panoramic roof either doesn't close all the way, stay up to let the air come underneath it to introduce the risk of it flying away, or become really flappy when driving with open roof.
Other or unspecified, Jul 8, 2021
On July the 8th I was driver on interstate highway 65south in Birmingham Alabama in my 2015 Mercedes c 300 when there was a loud thump which startled me and almost caused an accident what happened is the roof panel between the windshield and sunroof flew off it caused damage to my vehicle and almost an accident now when I contacted Mercedes they say that it is a recall out for this problem but they do not have a time as to when this can be fixed this will be a problem because now I am not able to drive my vehicle because there is a gape between the windshield and the roof where water and anything else will get into the vehicle this is terrible now I am without a car for who knows how long.
Engine, Jul 5, 2021
In March of 2020 I was driving home from work. I stopped at a red light. When it turned green, I proceeded to step on the gas. My car started making noises and shaking as I drove. My check engine light came on. I was able to pull over without incident. My vehicle has under 48k miles on it! I had it towed to a Firestone facility by my house. They replaced spark plugs and ignition coil 1 and 2. They said it was still severely misfiring. Cylinder 1 must have internal damage and should be towed to the dealer. They gave me a spark plug they removed that had significant damage to the top part. They said something must have impacted it with significant force. I then had the vehicle towed to a Mercedes Benz Dealership. They said they inspected with a scope and found piston material missing, can see ring exposed and have damage to cylinder wall. Will need to replace engine, turbo charger, cat converter intake manifold to repair. They wanted $18k to repair. I did some research and found out that the 2015 Mercedes C class was the first year they switched from 6 cylinder to 4 cylinder turbo charge engine. These models have had a significant amount of engine problems and failures, the manufacturer is aware of. Many of these occurred in cylinder 1 along with wrist pins issues and others. I found my situation wasn't unique. I then filed a complaint with The BBB in Georgia. MBUSA offered me $3k towards the repair or purchase of a new vehicle. I declined the offer. I only wanted my vehicle repaired. I wasn't alone in this situation. These issues are easily found online. My vehicle has since been sitting in my driveway for almost a year and a half. I've been making my monthly car and insurance payments on a vehicle I can't drive. I recently went to the Mercedes dealership and they will give me $5k for the vehicle towards a trade, leaving me with $15k negative equity towards the purchase of a vehicle. Mercedes should stand behind their products and do the right thing