2012 Mercedes-Benz C 300

From 2000 through 2017, Takata produced millions of air bag inflators using two types of phase-stabilized ammonium nitrate ("PSAN") propellant -- propellant 2004 and propellant 2004L. After prolonged exposure to high temperature cycles and humidity, inflators using propellant 2004 can degrade, causing the propellant to burn too quickly when ignited. The rapid burning can cause the inflator to rupture during deployment, potentially causing serious or even fatal injury to vehicle occupants. See 2016 Blomquist Report at www.nhtsa.gov/sites/nhtsa.gov/files/documents/expert_report-hrblomquist.pdf.Consequently, all frontal inflators using propellant 2004 that do not contain a "desiccant" (a substance that traps and holds moisture) in US vehicles are under recall. These "non-desiccated" inflators either have been or are required to be replaced.In some cases, the remedy part for these recalled inflators was, or will be, an inflator using either propellant 2004 or 2004L that does contain a desiccant. None of these "desiccated" remedy parts (which were installed in older model year vehicles) are currently under recall for a degradation concern. Certain subsets of desiccated PSAN inflators using propellant 2004 for use as original equipment, however, have been recalled for a degradation concern. All Takata inflators produced with propellant 2004L contain desiccant, and none of these desiccated inflators using propellant 2004L are under recall for a degradation concern. There have been no reported field ruptures in any non-recalled desiccated PSAN inflators.It is understood that desiccants fully saturate at some threshold, at which point any additional moisture will not be captured. This means the degradation process observed in non-desiccated inflators using propellant 2004 may also occur in non-recalled desiccated inflators using propellant 2004, assuming additional moisture enters the inflator and high temperature cycling occurs. Based on available information, desiccant saturation can occur within the first five years in the worst environments, and the time required for full saturation is affected by multiple factors. While no present safety risk has been identified, further work is needed to evaluate the future risk of non-recalled desiccated inflators using propellant 2004.Three entities -- Takata (now known as TK Global), the Independent Testing Coalition, and Exponent -- have been studying the long-term behavior of Takata desiccated PSAN inflators using propellant 2004L (as well as 2004) in the presence of moisture and temperature cycling. The research efforts, which include development of predictive modeling techniques and field sample analysis, are ongoing. To date, none of the researchers have identified field evidence showing that propellant 2004L is undergoing a degradation process that leads to aggressive deployment and potential rupture. However, the time in service of such inflators remains short compared to that of the inflators using propellant 2004. Further study is needed to assess the long-term safety of desiccated inflators using propellant 2004L.The Office of Defects Investigation is opening this investigation to examine whether a safety defect related to propellant degradation exists in non-recalled desiccated PSAN frontal inflators manufactured by Takata. This investigation will require extensive information on Takata production processes and surveys of inflators in the field. Lists of recall actions that may have used desiccated PSAN inflators as remedy parts, as well as the makes and models originally manufactured with them, is available with the downloadable version of this document (see nhtsa.gov/recalls?nhtsaId=EA21002 -- note this information is subject to change/revision as the investigation proceeds). This investigation does not supersede EA15-001, which remains open.

Vehicle: 2012 Mercedes-Benz C300 4Matic Sport Problem Component: Fuel / Propulsion System Safety Issue Description: My 2012 Mercedes-Benz C300 developed a serious fuel tank leak at approximately 106,460 miles which created overwhelming gasoline fumes and rendered the vehicle unsafe to operate. The gasoline fumes were extremely strong and entered the passenger area. The fumes were severe enough that I became physically overwhelmed from the gasoline exposure and discarded clothing due to gasoline contamination and odor. A local repair facility identified the leaking fuel tank. I was informed the replacement fuel tank was allegedly on extended backorder through Mercedes-Benz channels. Because the vehicle was unsafe to drive and replacement parts were allegedly unavailable for several months, I was forced to tow the vehicle from [XXX] to [XXX] at my own expense in order to locate a repair facility that could obtain a replacement fuel tank and safely repair the vehicle. The repair invoice states: “Installed used lt fuel tank incl switchover fuel pumps replace section of steel fuel line front of tank from lower braided line.” I am submitting this complaint due to: serious gasoline leak safety concerns, severe gasoline fume exposure, potential fire hazard, and the alleged extended unavailability of replacement fuel tanks. Mercedes-Benz USA Case Number: 22302114 INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11738871

Incident

Apr 26, 2026

I have a rust free, relatively lower mileage car I bought for my teen daughter. Despite being such a clean car the rear subframe has rusted and rear suspension has broke off while driving, hitting the fuel tank and is unstable. We avoided an accident but the car is not drivable.

NHTSA ID

11732281

Incident

Apr 10, 2026

Mercedes of Danbury replaced the rear sub frame CODE 3441 47, since my mechanic (Newtown Auto Repair) told me that the Front subframe is in real bad shape, rotten/rusted, that it is dangerous to drive the car in this condition since the wheel and steering components are part and attached to it, the car would be out of control and all over the road any of these components fail and pull / brake away from the rusted out Sub Frame. When I brought the car in was under the impression that Mercedes Benz would replace front and back Sub Frames. But now they informed me of only recall on rear subframe, rear subframe will let go wheels will collapse, front controls the car and failing could kill people and total the car. frames.

NHTSA ID

11701264

Incident

Nov 20, 2025

The contact owns a 2012 Mercedes-Benz C300. The contact stated the fuel tank was emitting a fuel odor. The contact stated that the fuel odor was extremely strong and could be smelled inside the residence while the vehicle was parked in the garage. There were no warning lights illuminated. The vehicle was taken to a Certified Mechanic, who diagnosed that the leak was coming from the top of the fuel tank; however, the mechanic was unable to specify the cause. The vehicle was towed to the dealer, but the vehicle was not diagnosed. The vehicle was not repaired. The contact became aware of NHTSA Campaign Number: 12V557000 ( Fuel System, Gasoline) online; however, the VIN was not included. The manufacturer was informed of the failure and informed the contact that the VIN was not under recall. The failure mileage was approximately 98,000.

NHTSA ID

11696118

Incident

Jul 28, 2025

Mileage

98,000 mi

Rear subframe rotted out and broke due to corrosion. Rear crossmember is broken and needs replaced. My safety as well as the safely of other was put at risk. Loss of control at high speed could have been deadly. Luckily, I wasn’t going very fast at the time of incident or else who knows what would have happened to me or bystanders. Independent service center inspected and confirmed that incident was due to corrosion in the rear. They informed me of the extended warranty (20 years, unlimited miles) on 2008-2015 C300 models for this particular issue as my safety and the safety of others was put at risk. There were some symptoms leading up to the incident. At the time of braking the car would become unstable and feel skittish in the rear. It felt as if the rear was sliding to one side. The vehicle would also make some metal clinking noises at sharper turns. The symptoms had been more frequent in the prior 2-3 months of incident. The vehicle has been inspected and diagnosed by one shop and is currently getting a second opinion from another independent service center.

NHTSA ID

11682005

Incident

Jul 27, 2025

Rear subframe crossmember rotting, needs replacement. It seems to be a common problem with this vehicle and the assumption by most professional is that it a faulty part supplied by a third party to Mercedes. The rest of the cars undercarriage is pristine, making me wonder why just this one part would rust out.

NHTSA ID

11674095

Incident

Jul 16, 2025

I was driving normally last week when the driver's head restraint system (known by Mercedes as Neck Pro) unexpectedly and without warning blew at my head. The noise was very loud, and the headrest slammed against my head. Luckily, I was driving approximately 20-25 miles per hour, daytime, on a residential street without too many other vehicles. I was able to pull over to investigate what happened and ensure I wasn't injured and did not collide with any objects in the road. If this had happened on the highway at highway speeds with a less attentive driver, I could see this potentially resulting in a major collision. The road was fat, no bumps, weather was clear. There is no reason why this happened. From what I can tell, the system looks like it failed (plastic clips broke off) and the system did not intentionally deploy. It has not been repaired and is available for inspection. I have not taken it to the dealership for review. The vehicle is in perfect condition with no warnings. It very recently passed Maryland state inspection.

NHTSA ID

11673323

Incident

Jul 11, 2025

I was replacing rear tail light bulb. Now I'm getting an error message on instrument cluster. I tried to fix the issue but couldn't do to the fact the wiring harness has melted. Mercedes Benz had a recall back in 2013 saying this is a safety issue. No recall for our car.

NHTSA ID

11661547

Incident

May 16, 2025

Single throttle lift-off clunking noise from the side shaft when moving off (audible at the outboard end). The noise is heard once in each instance when changing direction of travel. Note: Sound file in attachment Cause If the complaint is eliminated by experimentally loosening the outboard collar nut (by 1 turn), the problem is due to cracking of the microweld between the wheel bearing inner race and the joint housing of the side shaft. Note: The collar nut must always be replaced after being loosened. See also LI33.20-P-078406 Remedy Coat contact surface of side shaft with wheel bearing with Molykote paint. To do this, proceed as follows: 1. Remove side shafts 2. Clean contact surface A (see image file in attachment "Outer joint housing before") before coating with Molykote, using "spirit" (free of dust and grease) 3. Coat contact surface A (see image file in attachment "Outer joint housing after") with Molykote and leave to dry for "one hour" in removed condition 4. Reinstall side shafts Note: Before using the antifriction coating (Molykote), stir it or shake it thoroughly for (at least 1 minute).

Complaint Creaking noise, in irregular sequence when driving slowly in combination with slight steering movements and/or Creaking/crackling noises from the area of the wheel bearing on the front axle when cornering/ maneuvering. Sound file attached for comparison. MUST match noise for proper diagnosis. NOTE: Steering functionality is not affected. Cause Contact area between wheel bearing and steering knuckle. See also: LI35.30-P-058566 (Throttle Lift-Off Noise - Rear) LI33.30-P-056665 (Throttle Lift-Off Noise - Front) LI40.10-P-059248 (Wheel cracking noise when cornering) Remedy 1. Perform Operation A and evaluate by testing vehicle. 2. If noise is still present after re-testing: • If 192/232 chassis, verify FIN is in the listed range below in "Operation B" and perform. • If not 192/232 chassis or vehicle is a 192/232 not in the listed FIN range, additional verifications of where the noise is coming from are needed. Use multiple channel NVH method to narrow down location. Verify the LI's listed above were completed or if there are other similar noises associated with the chassis (Example: 192/232 also has under panel noises and an associated LI). Operation A: 1. Clean contact surfaces of wheel bearing and steering knuckle with brake cleaner (see areas marked blue in pictures "2.jpg" and "3.jpg"). NOTE: The front area of the wheel bearing and the seals must not come into contact with the cleaner, otherwise, the sealing rings will be damaged. 2. Clean threads of wheel bearing mounting. 3. Thinly coat contact surfaces of wheel bearing, steering knuckle, and axle mating face with Molykote (annular joint grease) (see areas marked blue in pictures "2.jpg" and "3.jpg"). NOTE: Axle mating face greasing is also covered in LI35.30-P-058566 and LI33.30-P-056665. Operation B (Only applies to 192 and 232 in listed FIN range): Only affects vehicles up to FIN end number: • Model series 192: xxx xxx xx 002 876 • Model series 232: xxx xxx xx 022 312 1. Replace steering knuckle. 2. Wheel bearings do not need to be replaced.

Complaint There are several types of complaint about noises or poor windshield wiper wiping performance: A: Wiper blades squeaking, chattering, shuddering B: The windshield is not wiped completely (streaking) C: During the downward movement water is pulled back onto the windshield from the A-pillar (Figure 1) D: After windshield cleaning, water keeps spraying onto the windshield for several wipe cycles (Figure 2) A1: The windshield and wiper blades are contaminated with residues from car washing facilities, identifiable by the water beading. The resulting differences in the friction values between the wiper blades and the windshield can excite the wiper blades to vibrate. Note: It is mostly wax residue from the washer system, but also water-repellent nano-particle coating for paint and/or silicone-based washer fluid, that could cause this problem. A partially dry windshield also has different friction values, which can likewise result in squeaking of the wiper blades A2: The wiper blades are worn by mechanical damage (wiper lip damaged by ice or insect debris, or deformed by long periods of disuse). A3: Incorrect angle of incidence of the wiper arms to the windshield. Because of this, the rubber lip of the wiper blade may not flip over at the reversal point. Cause B: B1: Wax/ dirt residues on the windshield B2: Wiper blades deformed or worn B3: Downforce of wiper arm not OK (Figure 3) Cause C: Water is pulled back onto the windshield by the differential pressure created as the wiper arm moves downwards. Cause D: Washer water collects in the fastening of the wiper blade and is blown onto the windshield by the airstream over several wipe cycles. Note and supporting information: Wiper blades are wear parts which, even when "not used" for long periods (kept in park position), may become permanently deformed and damaged. Further stresses on the rubber wiper blade arise due to various environmental influences which progressively change the effectiveness of the rubber wiper blade and accelerate the aging process. Due to the natural aging process and wear, the wiper blades should be replaced twice a year, preferably in Spring and Fall (see operator's manual). Remedy Remedy A: A1: Cleaning entire windshield with A 000 986 40 71. A2: Checking water's flow behavior after windshield has been cleaned (see Video 1). If, after cleaning, there are still areas with water beading, then the cleaning process must be carried out again until a rejection reaction is no longer present. • Note: On the vehicle in the video (Video 1), water still beads on the bottom left of the windshield. The windshield is still not properly clean, even though it appears to be clean. The windshield is only properly clean when there are no more areas on the windshield where water beads. A3: Replace wiper blades with genuine wiper blades. Important: Only exchange wiper blades if windshield no longer has water-repellent areas Note: Replacement of wiper blades is not covered under warranty and can be replaced at the expense of the customer. Remedy B: B1: Clean windshield with intensive cleaner A 000 986 40 71. Important: Do not clean the wiper blades otherwise the graphite coating will be damaged. B2: Replace wiper blades with genuine wiper blades • Note: Replacement of wiper blades is not covered under warranty and can be replaced at the expense of the customer. B3: Check the wiper arm for excessive resistance in the bearing. Restore mobility or replace wiper arm if necessary. Remedy C: Problem inherent in design for which there is no technical remedy. Exception: X204 up to 02/2014. In these vehicles, it is possible to install the design configuration of vehicles as of 02/2014. This includes wiper arms (styled arms) with improved behavior in this respect. It is also necessary to replace the wiper blades because the styled arms feature a Top Lock connection (previously Side Lock).

Complaint Potential corrosion on the rear axle carrier Cause Due to market-specific conditions such as moisture, ingress of dirt and/or environmental influences, corrosion can occur on the rear axle carrier Remedy In the event of a complaint, the optimized repair method must be used when replacing the rear axle carrier. The repair method for the respective model series can be found in the attachment. Repair packages are available in Xentry Repair Packages for the special processing of rear axle carriers Note: Please utilize flexible wand (319-SAT1058826) along with the Cavity Preservation Gun (W 000 588 03 72 00) for cavity wax application to improve coverage and reduces labor efforts. The flexible wand may be obtained through the Mercedes-Benz Standard Service Equipment Program website.

Complaint Creaking noise, in irregular sequence when driving slowly in combination with slight steering movements and/or Creaking/crackling noises from the area of the wheel bearing on the front axle when cornering/ maneuvering. Sound file attached for comparison. MUST match noise for proper diagnosis. NOTE: Steering functionality is not affected. Cause Contact area between wheel bearing and steering knuckle. See also: LI35.30-P-058566 (Throttle Lift-Off Noise - Rear) LI33.30-P-056665 (Throttle Lift-Off Noise - Front) LI40.10-P-059248 (Wheel cracking noise when cornering) Remedy 1. Perform Operation A and evaluate by testing vehicle. 2. If noise is still present after re-testing: • If 192/232 chassis, verify FIN is in the listed range below in "Operation B" and perform. • If not 192/232 chassis or vehicle is a 192/232 not in the listed FIN range, additional verifications of where the noise is coming from are needed. Use multiple channel NVH method to narrow down location. Verify the LI's listed above were completed or if there are other similar noises associated with the chassis (Example: 192/232 also has under panel noises and an associated LI). Operation A: 1. Clean contact surfaces of wheel bearing and steering knuckle with brake cleaner (see areas marked blue in pictures "2.jpg" and "3.jpg"). NOTE: The front area of the wheel bearing and the seals must not come into contact with the cleaner, otherwise, the sealing rings will be damaged. 2. Clean threads of wheel bearing mounting. 3. Thinly coat contact surfaces of wheel bearing, steering knuckle, and axle mating face with Molykote (annular joint grease) (see areas marked blue in pictures "2.jpg" and "3.jpg"). NOTE: Axle mating face greasing is also covered in LI35.30-P-058566 and LI33.30-P-056665. Operation B (Only applies to 192 and 232 in listed FIN range): Only affects vehicles up to FIN end number: • Model series 192: xxx xxx xx 002 876 • Model series 232: xxx xxx xx 022 312 1. Replace steering knuckle. 2. Wheel bearings do not need to be replaced.

Complaint Headlamp, front fog lamp leaky or fogged. Cause Fogging of the headlamps is a natural phenomenon, which can occur under certain climatic conditions. It does not lead to any technical impairment of the headlamp. If a pressure compensation diaphragm is fitted in the housing cover, then the lamp unit is a "closed system". Remedy Headlamp: Remedy 1 Clearing fogged/condensed LED headlamps: 1. Drive vehicle into workshop (temperature higher than +18 °C/+64.4 °F) and connect the exhaust extraction. Note: Do not perform an engine wash before the defogging test. 2. Switch off the engine and connect battery support via a charger. 3. Open the hood. 4. Switch on the lights. 5. Leave the vehicle in this state for 60 minutes. 6. Check for formation of condensation, a significant reduction in the formation of condensation must be clearly recognizable (thawing progress). Clearing of fogged/condensed LED headlamps and LED rear lamps on electric vehicles: 1. Drive the vehicle into the workshop (temperature higher than +18 °C/+64.4°F). 2. Connect battery backup via a charger. 3. Open the front-end flap and ensure sufficient ventilation. 4. Switch on the lights. 5. Leave the vehicle in this state for 60 minutes. 6. Check for formation of condensation, a significant reduction in the formation of condensation must be clearly recognizable (thawing progress). Clearing fogged/condensed halogen/xenon headlamps: 1. Drive the vehicle into the workshop (temperature higher than +18 °C/+64.4°F). Note: Do not perform an engine wash before the defogging test. 2. Switch off the engine. 3. Open the hood. 4. Switch off the lights. 5. Leave the vehicle in this state for 60 minutes. 6. Check for formation of condensation, a significant reduction in the formation of condensation must be clearly recognizable (thawing progress). Note: If there is no visible reduction in condensation, check the headlamp for malfunctions. (see Remedy 2) It is not physically possible to defog the headlamps completely. Fogging does not impair the operation or the service life of the headlamp. Note: Only implement Remedy 1 for model series 463 (from model year 2018) and model series 465. Remedy 2 A defective headlamp can be identified as follows: 1. Check the headlamp for external damage and that the cover caps and the diaphragm are correctly seated. 2. Check the electrical connectors of the plugs and pins. 3. Check for leak tightness according to LI82.10-P-078307. The test can only be conducted on headlamps. 4. If the headlamp or the rear lamp has any external damage, replace the component part in accordance with the WIS instructions. Note: External damage to the headlamp/rear lamp or faulty seating of the cover caps does not present a warranty or goodwill case. Note: With headlamps, it is possible to install desiccant packs if the problem occurs repeatedly. • Open ventilation system LI82.10-P-078302 • Closed ventilation system LI82.10-P-078304