2012 Mercedes-Benz C-Class
Problems, recalls and owner-reported issues
Air bags is the leading concern among 587 owner complaints filed for this model year. This is the 3rd highest complaint count among 23 C-Class model years with reports.
Of the 2012 reports, 8 involved a crash and 7 involved a fire. 10 people were injured and 1 person died.
What owners report most often
Recalls and investigations
No safety recalls on file.
Representative owner complaints
587 reports, newest first.
Structure, Oct 27, 2022
I have a 20212 Mercedes C300 with 70,000 miles. I took it into the MB dealership for inspection and was told that the rear subframe was rusted through. The subframe's failure also caused the brake lines to rust to the point of needing to be replaced. The subframe repair will cost $5,900 and the brake line replacement will cost around $1,200. The dealer told me the car couldn't be driven safely, so I had to leave it there to be repaired. There were no interior warning alarms about the structure or the brakes. According to forums on Benzworld.org, this is a known problem on these specific cars and the component is replaced for free by MB in Europe.
Fuel/propulsion system, Oct 23, 2022
Car is leaking gas very dangers . I contact Mercedes dealer regarding the recall on this type of Mercedes i have and they said only vehicles manufactured from April 18, 2011, through July 12, 2011. Mine was before or after , and they refuse to give me the exactly date for my car manufacturer. Car I use for Uber , and i don’t have any other income . If someone just through away a cigarette in parking lot might cause a big problem in the building and others cars in parking
Suspension, Oct 19, 2022
I went to my dealership for a routine yearly service appointment, which I do regularly, along with yearly inspections. My car was purchased new to my liking in 2012 with input from my late partner who passed before I received it! I waited quite some time to get my gem. When it arrived, I had all I could do to drive it, given my loss. I garage it every day for the last 10+ years, never left it outside, it is pristine, only has 64,000 miles on it. To my disbelief, was informed by the MB technician yesterday that I have corrosion on my left rear sub panel, and that I should not drive it and consider a trade-in - NO WAY!! And that the part would cost me over $4,800 to replace and it would not be available until February 2023. So, I should drive another car, which I do not have!!!!! After researching, I am beyond disappointed that this is a known MB manufacturer's defect that has gone this far, customer action needs to be taken!!! My local car dealership states they knew nothing about this, however; pointed out a number of Mercedes C300 in their parking lot sitting with the same life-threatening issue. They were eager for me to talk to sales for a trade-in. Go figure this strategy, NOT. I have had three Mercedes Benz which I love, I do not want to part with this gem, but my need to . . . Please do something . . . Safety and Life matters
Structure, Oct 18, 2022
The contact owns a 2012 Mercedes-Benz C300. The contact stated that the vehicle was taken to the dealer for a routine maintenance check and she was informed by the dealer that there was a hole in the subframe. The contact was informed that the subframe needed to be replaced. No warning light was illuminated. The vehicle was not repaired. The manufacture was not notified of the failure. The failure mileage was approximately 80,000.
Suspension, Oct 17, 2022
The contact owns a 2012 Mercedes-Benz C300. The contact stated that upon parking the vehicle at the dealer parking lot, she heard abnormal sounds coming from the rear of the vehicle. There was no warning light illuminated. The dealer diagnosed that the rear subframe was severely corroded and the rear control arm was detaching from the subframe. The dealer diagnosed that the subframe needed to be replaced. The vehicle was not repaired. The manufacturer was notified of the failure and referred the contact to the NHTSA Hotline. The failure mileage was approximately 79,000. The contact was informed by the service advisor that the vehicle should not be driven until it is repaired due to the extensive damage to the subframe.
Engine, Oct 13, 2022
Faulty camshaft adjusters creating timing chain to stretch and tensioners to fail , causing excessive wear to the crankshaft and wear of the teeth resulting in catastrophic damage and complete engine failure ( I have not replaced this timing chain or camshaft adjuster yet but i can hear the timing chain rattling from the defective parts from manufacturer. )
Suspension, Structure, Oct 12, 2022
Rear Subframe Cracking in Mercedes Benz 2012, C- Class, Sports. It can be life threatening for driver and passengers. Cost is $5700 for repairs. This replacement is free in Europe and Canada.
Fuel/propulsion system, Oct 11, 2022
My Mercedes 2012 C 300 is leaking gas which may lead to fire ( the fuel filter flange when operated in high temperatures
Suspension, Structure, Other or unspecified, Oct 10, 2022
Rare Subframe breaking off parts are not available for at least 6 months. I have kids and mechanics advise me to keep it off the road. My only means of transportation
Suspension, Oct 6, 2022
the back sub frame rotted away from rust
Suspension, Structure, Oct 3, 2022
The contact owns a 2012 Mercedes-Benz C300. The contact stated that while having an oil change performed on the vehicle by an independent mechanic, he was informed that the cross member was severely corroded. The contact was informed by the mechanic that the vehicle was unsafe to drive. Neither the dealer nor the manufacturer had been notified of the failure. The vehicle was not repaired. The failure mileage was approximately 125,000.
Other or unspecified, Sep 23, 2022
the rear subframe rotted away
Structure, Sep 22, 2022
The contact owns a 2012 Mercedes-Benz C300. The contact stated that the vehicle was taken to be serviced under an unknown recall however, the mechanic informed him that the rear subframe was severely rusted, creating holes in the subframe. The dealer diagnosed that the subframe needed to be replaced. The vehicle had not been repaired due to the part being on backorder. The manufacturer was made aware of the failure and informed the contact that there was no recall or warranty coverage for the failure. The approximate failure mileage was 65,500.
Suspension, Sep 19, 2022
Diagnosed with broken rear sub frame: "Broken rear sub frame, left side lower link is broken off and contacting Fuel Tank. Rear tires are also bald and care is unsafe to drive". Recall in Canada, but not USA. Sub frames on backorder until January 2023. I have three years of payment left, and am now being quoted 6,300 from the MB Service Ctr in Wilmington DE to fix this problem. Again, the items are on backorder due to heavy demand. Im a single mom we depend on my car to get us to work. This is the ultimate catch 22 as the car is extremely dangerous to drive and put us all in serious jeopardy - but no one will take this broken car as a trade in. I am forced to drive the vehicle while I wait for backordered parts and pray that I can get a loan to pay for it. "".....and contacting the fuel tank".....
Other or unspecified, Sep 16, 2022
The W204 subframe of my Mercedes Benz C Class is failing and in need of repair, this should not be happening to a car with less than 80K miles on it. My local auto repair shop which exclusively services Mercedes Benz currently has two vehicles with the same issue and informed me that the subframe part is currently out of stock due to the number of failures. This issue has caused a recall in other countries. What is the NHTSA doing about this issue. I will be contacting my congressional representative today as well.
Suspension, Sep 14, 2022
The contact owns a 2012 Mercedes-Benz C300. The contact stated while driving 25 MPH going downhill, the rear end of the vehicle shifted independently to the right. The contact stated no warning light was illuminated. The contact was able to continue driving at a slow speed to her destination. The contact stated her husband inspected the vehicle and became aware that the rear subframe cross member had fractured due to corrosion. The vehicle was not diagnosed or repaired. A dealer was not contacted. The manufacturer had been informed of the failure. The failure mileage was approximately 149,000.
Suspension, Sep 13, 2022
Subframe corroded/rusted out. Car is in excellent condition with no other rust or corrosion. Car has 58,800 miles and regularly maintained by dealer. Took car to TireDiscounter because of noise. Mechanic put car on lift and reviewed corrosion and other damaged cause by failed part. Mechanic called MB service department and was told that parts on 5- 6 months back order because of this issue. But no recall even though problem is wide spread. Rear tires and gas tanked damaged by loose subframe.
Structure, Sep 12, 2022
- Right Rear Subframe; Yes, available for inspection. - My mechanic told me that driving the car more than 2 miles or at a high rate of speed was very dangerous. He told me there that if the car braked quickly or was driven at a high rate of speed that there was a very good chance of an accident. There is a risk of the right control arm detaching from the frame; this could cause the car to be uncontrollable with the right rear wheel and control arm detaching from the vehicle. - Yes, the issue was confirmed by my mechanic, who works at an independent service center. - No. - There were no warning lamps or messages. I had begun to hear a loud clunking noise, usually when braking.
Structure, Sep 10, 2022
I’m filing a complaint due to a concern regarding the rear subframe of my vehicle becoming rotted/rusted out and falling apart at any time. This is due to a Mercedes Benz manufacturing issue where they tried cost cutting which turned out very poor quality materials for this very important assembly. I have researched online about this problem, and turns out, it is very common with this body style c300 ('08 - '14). There are hundreds, if not thousands, of individuals within the USA who are having this exact same issue with as little as 60,000 miles. Most are happening around the 90,000 mile mark however. They primarily mention in many online forums how scared they were when it happened and how lucky they are it didn’t cause a major accident…yet. My car only has ~110,000 miles and is just about 10 years of age. This issue should never happen for a vehicle with such low miles and such a short life, especially from a prominent and distinguished automotive company. This is a Huge Safety Concern, and I am Scared that this subframe will fail without warning and at a high speed, which can likely cause me to be involved in a major accident where people are killed or seriously injured. It is astonishing how this subframe was not recalled by now and how Mercedes USA has not taken responsibility for this. This issue needs to be addressed and recalled Immediately before people are killed or seriously injured, and before more of these parts break. Please look into this very soon as this is a very serious matter.
Structure, Sep 9, 2022
The contact owns a 2012 Mercedes-Benz C300. The contact stated that the vehicle was taken in for a routine service check at the dealer and the mechanic informed her that the rear subframe was rusted and the vehicle was unsafe to drive. The contact was informed that the part was on back order. The manufacturer was not contacted. The failure mileage was 119,000.
Suspension, Sep 8, 2022
I ran off the road and my rear suspension sub frame literally broke in half. Upon further research I’ve learned that these parts are faulty and several people have had theirs rust completely in two. Mine had lots of rust damage and that is likely what caused the damage to mine when I ran off the road (MINOR impact that should have never caused that much damage). Mercedes has recalled this part in several countries including Germany and Canada. When I drove home after running off the road my car was nearly impossible to drive. It was jerking all over the road and when I tapped the brakes the rear end of the car would come up off of the road (into the air)! This was in June. It’s now September and I still have not been able to obtain a part from Mercedes. So many people are having this issue with their vehicles that the part is on back order until Q1 of 2023. This is a part of the cars sub frame that is rusting in two! One would argue a broken sub frame is dangerous. And it’s such a prominent issue the part is on back order. Furthermore, Mercedes has changed the type of metal used in replacement parts, which is an acknowledgment of the parts defect.
Steering, Sep 7, 2022
The esl/eis failed. Turned car off and after coming back to try and turn it on, it didn't work. Steering wheel was locked and car wouldn't engage with key. After checking with mechanics and checking online, I discovered that it is a frequent issue that happens with no warning whatsoever. Which is quite worrisome to think the Steering wheel could lock at anytime without notice. My car is a 2012 Mercedes c250 coupe.
Structure, Sep 6, 2022
the Rear Subrame CRACKED while Driving, Almost causing a Major accident with my son in the car as well. This seems to be a MAJOR problem being overlooked and ignored by Mercedes Benz . This repair is going to Cost me $ 3000-$ 5000 Dollars. and the Replacement Subframe is Impossible to find and on Back order ! so Now I'm without a Vehicle for God knows How long ?? I Feel there is No Doubt this is a Defect and Should be Covered by Mercedes Benz and a Recall ! How is this not being investigated is Really Scary. How can a Frame or a Car just Crack ? That's Not safe for ANYBODY !
Structure, Sep 3, 2022
During a routine oil change Mercedes mechanic discovered our rear subframe is rusted on both sides and needs to be replaced. This is apparently a well known problem, and Mercedes will replace this for free in Germany, but has not recalled the subframes in the US. Mercedes created a new OEM part as the replacement part, proving the original part is faulty. However Mercedes does not have enough parts ane every mechanic we have spoken with has several subframes on order for months at a time. We have waited 9 weeks at this point. Many Mercedes drivers subframes have broken making the cars undrivable.
Steering, Sep 1, 2022
The contact owns a 2012 Mercedes-Benz C300. The contact stated that the vehicle was unable to start-up as needed. The vehicle was towed to the dealer where it was diagnosed with a faulty steering column sensor that needed to be replaced. The vehicle was not repaired. The manufacturer was not made aware of the failure. The failure mileage was 104,692.