2013 Mercedes-Benz C300 Problems

What owners report

Owners of this model year most often describe rear subframe corrosion, which shows up as noise, a loose rear end, or pulling to one side when braking, frequently in the 60,000 to 100,000 mile range and sometimes discovered during routine service. Airbag-related complaints are also common, mostly warning lights or the passenger-seat airbag message switching on and off, along with a number of recall and parts-availability complaints.

1. 1
   Body and structure

   Rear subframe corrosion and rust-through

   • 111 complaints (42%)
   • median 82,000 mi at 9.7 yrs old (25 state mileage)
   • 1 mention a crash, fire or injury
   • owner-quoted repair $4,474 (median of 14 quotes)
   • filed 2021–2026

   Owners describe the rear subframe rusting through, sometimes to the point of holes, a fractured control link, or the rear of the car sagging onto the fuel tank. Many mention abnormal noises, a rear end that feels unstable or fishtails, and the car pulling or veering to one side when the brake pedal is pressed. Several say the problem was found during routine service or by an independent mechanic, and some note a warranty extension or partial cost coverage being discussed, while others were told it was not repaired. Most often reported between about 50,000 and 160,000 miles, usually on older cars in areas with moisture and road salt.

   4 related service bulletins

   What to check: Ask for a pre-purchase inspection that specifically looks at the rear subframe for rust and holes, and check whether the subframe warranty extension has been used. Listen for rear-end clunks and note whether the car tracks straight when braking.

   2 excerpts from owner complaints in NHTSA records

   “The rear subframe rusted through risking the control arms from detaching from the frame. This could cause the car to be uncontrollable with the right, rear wheel and control arm from detaching from the vehicle.”

   NHTSA complaint #11414126, filed 2021-04, 99,000 miles

   “The contact owns a 2013 Mercedes-Benz C300. The contact stated that while the vehicle was at the dealer for routine maintenance, the dealer informed him that the subframe was corroded and needed to be replaced. The vehicle was not repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 89,000.”

   NHTSA complaint #11484447, filed 2022-09, 89,000 miles
2. 2
   Air bags

   Airbag warning light and passenger-seat occupancy issues

   • 83 complaints (32%)
   • median 68,031 mi at 5.2 yrs old (19 state mileage)
   • 6 mention a crash, fire or injury
   • filed 2013–2025

   Owners describe the airbag warning light or the passengside airbag indicator coming on or switching between enabled and disabled with an adult seated, sometimes intermittently. Complaints mention a message telling them to service the airbags, and dealers identifying a sensor or module fault; several also describe long waits for parts or being told a vehicle identification number was not covered by a recall. Some recount the airbag turning off at the dealer while parts were unavailable. Reported across a wide mileage range, from a few thousand miles to over 130,000 miles, often appearing intermittently while driving or parked.

   Recall 17V627000Recall 19V010000Recall 18V0430001 related service bulletin

   What to check: Watch for any airbag warning or passenger-seat airbag message during a test drive, and ask whether the open airbag recalls for this vehicle have been completed and documented. A scan tool check of stored airbag fault codes is worthwhile.

   2 excerpts from owner complaints in NHTSA records

   “I was driving down the road at 15mph and the airbag in the drivers steering wheel deployed for no reason. Mercedes declines to complete an inspection and offered to replace and return the vehicle to me. I am concerned with the decision to not complete an inspection due to the severe nature of the situation. I was burned and bruised on my left arm and swerved into the other lane due to the shock of the airbag deployment. I am not comfortable driving the vehicle and I do not feel that it is safe.”

   NHTSA complaint #10747991, filed 2015-08, 28,000 miles

   “I received a recall inovember 2017 and am unable to get mb to make an appointment to fix an insufficient grounding component in the steering wheel which may causes an electrostatic discharge which deploys the takata airbag with resultant accident occurrence. I am in fear when driving. Mb has not responded to my request. They have not provided me with a safe car; they have ignored requests; they have given no answer to my letter and phone calls to ceo exler in atlanta or any person in manhattan main office. …”

   NHTSA complaint #11084481, filed 2018-04, 22,000 miles
3. 3
   Brakes

   Unintended acceleration and brake response complaints

   • 18 complaints (7%)
   • median 24,000 mi at 3.8 yrs old (11 state mileage)
   • 5 mention a crash, fire or injury
   • filed 2014–2026

   A cluster of complaints describes the car accelerating while the brake pedal was pressed, typically at low speed while parking or turning into a lot, with the brake pedal failing to slow the vehicle and the car striking a building or another vehicle. Others describe the accelerator becoming unresponsive, with traction and ABS lights coming on, and dealers pointing to connector pins or throttle body diagnosis. Reported at low mileage, mostly under about 25,000 miles, often at parking-lot speeds.

   What to check: Test the brake pedal feel and throttle response at low speed in an open area, and ask for any service history covering throttle body or ECU connector repairs.

   2 excerpts from owner complaints in NHTSA records

   “I barely stepped on the gas and vehicle accelerated real quickly. It was pretty scary it happened 2 times already. I do have a heavy foot so I am trying to monitor if I'm stepping on the gas too fast or hard.”

   NHTSA complaint #10651140, filed 2014-10, 26,500 miles

   “Problem identical to one in wethersfield ct. Listed as vehicle speed control. Happened to both my wife and myself on two separate occasions. My wife was driving up the driveway and ABS light came on and vehicle shut offt along with brakes not working and steering wheel unable to turn.one hour later after she left the car I went out and it started and all warnig light were out. My incident occurred on a city street prior to coming to a stop sign ABS light came on vehicle had no brakes steering or power. …”

   NHTSA complaint #10808848, filed 2015-12, 22,000 miles
4. 4
   Electrical system

   Water leaks into the cabin and electrical faults

   • 13 complaints (5%)
   • median 91,000 mi at 5.8 yrs old (9 state mileage, few)
   • 1 mention a crash, fire or injury
   • filed 2013–2025

   Owners report rain or washer water getting inside, from the sunroof, windows, or under the dashboard, sometimes soaking the front footwells. Complaints link this to electrical trouble, with multiple warning lights flashing, gauges dropping, turn signals failing, or an instrument panel short that a mechanic described as nearly catching fire. Some also mention a sunroof panel shattering while driving in rain. Reported from about 46,000 miles up to around 125,000 miles, often after heavy rain or a storm.

   Recall 19V7870001 related service bulletin

   What to check: Check for damp carpets and musty smells in the footwells and headliner, look at the sunroof drains and seals, and ask whether any water-intrusion or electrical repairs have been done.

   2 excerpts from owner complaints in NHTSA records

   “I have c 300 2013 mercedes which broke more than 3 times ( all within a year, this is a new car) with the same problem. This issue is potentially deadly to a driver. Acceleration diminished, breaks are not fully functioning, wind shield wiper don't work, signal does not work. I requested to get a new vehicle, but my request was denied. My understanding that mercedes does not care about my safety (or any other person who has this car) at all.I think this should be investigated further. …”

   NHTSA complaint #10588653, filed 2014-05, 13,000 miles

   “My mercedes benz c-300 4matic got rain water on the inside of the car and damaged the electrical. The car was parked on the street and all the windows was up. The drivers and passenger side of the car in the front under the dashboard was soaking wet from rain water. I do not know how the water got inside of the car. I was driving it after a rain storm and all the dash lights came on all the needle hands went down to zero, it was like the car was trying to restarting itself while I was driving. The car is now at mercedes benz novi michigan now. …”

   NHTSA complaint #11119816, filed 2018-08, 46,350 miles
5. 5
   Steering

   Steering loss or unresponsive steering

   • 23 complaints (9%)
   • median 57,802 mi at 5.2 yrs old (14 state mileage)
   • 2 mention a crash, fire or injury
   • filed 2013–2026

   Complaints describe the steering wheel failing to respond while turning, or the wheels no longer turning at all after the car is stopped and reversed, with the vehicle towed as a result. Others mention an electronic steering lock that would not release and prevented starting, and a dealer repair quoted as costly. Some report being told their vehicle was not included in the related campaign. Mostly reported between roughly 90,000 and 130,000 miles, though a few complaints come at lower mileage.

   Recall 17V252000

   What to check: During a test drive, turn the wheel lock to lock and confirm normal response, and ask whether the steering coupling bolt recall was performed. Also confirm the steering lock releases reliably on startup.

   2 excerpts from owner complaints in NHTSA records

   “The electronic steering lock failed while in the parked position. A tiny motor inside has burned up and it now prevents you from starting the vehicle. The dealership will not sell me a replacement to repair on my own and I must take it in to them for repair at a cost of over $1800.00. This is a very common defect failure in this series of 2008 to 2014 mercedes benz. I have a 2005 mercedes which does not have this problem with the unit and is operating correctly after 15 years.”

   NHTSA complaint #11337741, filed 2020-07, 93,000 miles

   “2013 C300 4matic luxury model. 1/26 - my engine stop while waiting for traffic light. (2nd trip of the day) it's not eco stop/start kind of stop. The car won't start when I release my brake and all the warning lights at dash were on. 1/29 - today when I started the car this morning the engine stop 1-2 seconds after I started it. (2nd trip of the day) all warning light at dash were on. I took out my key then plug in to start it again. This time engine started, but both engine and car shake looks like it?s going to stop. …”

   NHTSA complaint #10495131, filed 2013-01, 2,400 miles

Buying note. Have any example inspected for rear subframe rust before buying, since that is the most frequently reported concern and can affect how the car tracks and brakes. Confirm the open airbag and steering recalls have been completed, and check for prior water leaks into the cabin.

Summary written with AI from a sample of 60 NHTSA complaints for this model year (picked at random, with complaints that state a mileage and recent ones taken first), then checked automatically against the source records. Where a problem shows a complaint count, every complaint for this model year was matched with fixed keyword rules (written with AI and tested against the sample), and the mileage, age and repair figures are calculated from those complaints; owners' figures are as stated, not verified. Other counts refer to the sample. The excerpts come from NHTSA's public complaint records and are unverified; capitalisation is normalised, NHTSA staff notes are removed, and shortened text ends with “…”. Something wrong? Request a correction.