What 584 owners told NHTSA about the 2012 Mercedes-benz C-class Coupe

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.

NHTSA ODI 11489862

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.

NHTSA ODI 11489569

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. )

NHTSA ODI 11489131

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.

NHTSA ODI 11488998

My Mercedes 2012 C 300 is leaking gas which may lead to fire ( the fuel filter flange when operated in high temperatures

NHTSA ODI 11488867

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

NHTSA ODI 11488700

the back sub frame rotted away from rust

NHTSA ODI 11488123

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.

NHTSA ODI 11487590

the rear subframe rotted away

NHTSA ODI 11486014

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.

NHTSA ODI 11485892

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".....

NHTSA ODI 11485253

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.

NHTSA ODI 11484782

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.

NHTSA ODI 11484481

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.

NHTSA ODI 11484303

- 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.

NHTSA ODI 11484148

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.

NHTSA ODI 11483789

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.

NHTSA ODI 11483675

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.

NHTSA ODI 11483577

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.

NHTSA ODI 11483194

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 !

NHTSA ODI 11483036

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.

NHTSA ODI 11482722

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.

NHTSA ODI 11482411

Dealer states that the rear subframe has rusted and degraded to the point of requiring full replacement. The car is 10 years old with 98,000 miles on the odometer. This is premature degradation of an essential component.

NHTSA ODI 11482359

Took my car in for inspection at the Mercedes dealership. They advised the rear subframe was rotted or rusted. This occurred from the inside. The vehicle is garage kept. They advised Mercedes has no re-call on the issue in the United States. They are covering the issue outside the US. This is a major safety issue.

NHTSA ODI 11481592

The contact owns a 2012 Mercedes-Benz C300. The contact stated that the vehicle was taken to the dealer for an airbag inspection. During the inspection, the dealer informed the contact that the rear subframe was corroded. The vehicle was diagnosed and the contact was informed that the brake lines and rear subframe needed to be replaced. The vehicle was not repaired. The manufacturer was not notified of the failure. The approximate failure mileage was 120,000.

NHTSA ODI 11477748