RoadVitals

2015 Mercedes-Benz C400

Recalls, owner-reported complaints, investigations and safety data

Data refreshed

Owner complaintsComplaints are reports submitted to NHTSA by owners and drivers. NHTSA does not verify most reports before publishing them, and a complaint does not establish that a defect exists. Volume is influenced by how many of a vehicle were sold, how long it has been on the road, and how much attention an issue has received.
10
Latest Aug 8, 2025
Safety recallsA safety recall is issued when a manufacturer or NHTSA determines that a vehicle has a safety-related defect or does not comply with a federal motor vehicle safety standard. Recall repairs are free. Whether a specific vehicle is covered depends on its VIN — a recall listed for a model year does not necessarily apply to every vehicle of that year.
8
Latest Dec 15, 2023
InvestigationsNHTSA opens an investigation to examine whether a safety defect may exist. An open investigation is not a determination that a defect exists, and many investigations close without a recall. Investigations can, however, lead to one.
2
1 currently open
Crash or fire reportedComplaints whose submitter recorded that a crash or a fire occurred. These are the reporter's own answers on the NHTSA form, not verified findings.
0

Overview

Our database contains 10 NHTSA owner-reported complaints for the 2015 Mercedes-Benz C400, most frequently naming the body & structure, driver assistance and electrical categories. 8 safety recalls have been issued covering this model year; 2 NHTSA investigations name it; and 114 manufacturer communications are on file.

Complaints are reports submitted by owners and drivers to NHTSA. They are not verified and do not establish that a defect exists.

What owners report

Complaints grouped by the component NHTSA recorded

  • Body & structure654.5%
  • Driver assistance19.1%
  • Electrical19.1%
  • Engine19.1%
  • Suspension19.1%
  • Visibility19.1%

Percentages are of component mentions. A single complaint can name more than one component, so these do not sum to the total complaint count.

Safety recalls

8 campaigns cover this model year

Recalls apply to specific vehicles, not to every vehicle of a model year. Check your VIN with NHTSA or your manufacturer's dealer to confirm whether a recall affects your vehicle.

Check a VIN on NHTSA.gov

STRUCTURE:BODY:ROOF AND PILLARS

Dec 15, 2023
2,976 units potentially affected
The defect: Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2014-2020 C-Class, CLA, GLA, S-Class, GLC, and GLE vehicles. Please refer to MBUSA's recall report for specific vehicle details. The front roof panel located between the windshield and the panoramic sunroof may not have been bonded correctly to the vehicle during a prior repair, allowing the front panel to detach from the vehicle.
The risk: A detached roof panel can become a road hazard, increasing the risk of a crash.
The remedy: Dealers will replace the front panel, free of charge. Owner notification letters were mailed on August 2, 2024. Owner notification letters will be mailed in phases, on, March 22,2024, and August 2, 2024. Owners may contact MBUSA customer service at 1-800-367-6372. This recall is an expansion of NHTSA recall number 21V-197.
Mercedes-Benz USA, LLCView on NHTSA.gov

STRUCTURE:BODY:ROOF AND PILLARS

Mar 19, 2021
15,096 units potentially affected
The defect: Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2017-2020 C300 Coupe, C43 Coupe AMG, C43 AMG, 2015-2020 C300, GLA250, 2016-2018 C350e, CLA45 Coupe AMG, 2015 C400, S65 AMG, 2015-2019 C63 AMG, 2016 C450, 2015-2016 GLA45 AMG, S600, 2016-2020 GLC300, 2017-2019 GLC43 AMG, GLE43 Coupe AMG, 2014-2019 CLA250 Coupe, 2014-2015 CLA45 AMG, 2018 GLC63 AMG, 2014-2017 S550, 2018-2020 S450, 2016-2019 GLE63 Coupe AMG, 2016 GLE450 Coupe, 2014-2020 S63 AMG, 2018-2019 S560, and 2019 GLC350e vehicles equipped with a panoramic sunroof. The front roof panel located between the windshield and the panoramic sunroof may not have been bonded correctly to the vehicle during a prior repair.
The risk: The adhesive bonding of the front panel might deteriorate, possibly causing the front panel to detach from the vehicle and become a road hazard, increasing the risk of a crash.
The remedy: Mercedes-Benz dealer will remove the bonded panel and will install a new front panel by following the detailed repair instructions and using the approved primer, cleaner and adhesive, free of charge. Owner notification letters were mailed on September 3, 2021 and October 26, 2021. Owners may contact MBUSA customer service at 1-800-367-6372.
Mercedes-Benz USA, LLCManufacturer number 2021070010View on NHTSA.gov

COMMUNICATION

Nov 1, 2019
24,226 units potentially affected
The defect: Mercedes-Benz USA, LLC. (MBUSA) is recalling certain 2013-2017 vehicles due to a software fault that may cause the date and time for the emergency call system (eCall) to differ from the actual date and time, potentially relaying an inaccurate vehicle location. For a full list of the affected models visit: https://static.nhtsa.gov/odi/rcl/2019/RMISC-19V787-4620.pdf
The risk: An inaccurate vehicle location may delay emergency responders, increasing the risk of injury.
The remedy: MBUSA has initiated an Over the Air (OTA) remote update. MBUSA will also notify owners, and dealers will check software for a successful OTA or update the communication module software as needed, free of charge. The recall began December 23, 2019. Owners may contact MBUSA customer service at 1-800-367-6372. MBUSA's number for this recall is 2019120008.
Mercedes-Benz USA, LLC.Manufacturer number 2019120008View on NHTSA.gov

Safety investigations

NHTSA inquiries naming this vehicle. An investigation is not a finding of a defect.

EA21002OpenEngineering Analysis

Desiccated Air Bag Inflator Rupture

Opened Sep 17, 2021

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.

AIR BAGS:FRONTAL:DRIVER SIDE:INFLATOR MODULE
PE21001ClosedPreliminary Evaluation

Front Roof Panel Detachment

Opened Jan 8, 2021
Closed Oct 14, 2021

On January 8, 2021, after ongoing review with Mercedes Benz, the National Highway Traffic Safety Administration (NHTSA) Office of Defects Investigation (ODI) opened PE21-001 to assess allegations of front roof panel detachments while driving at highway speeds in certain 2015 Mercedes-Benz (Mercedes) C-Class vehicles.The subject front roof panel is a stationary panel composed of polycarbonate and is attached to the vehicle via adhesive at the time of manufacture. The panel is found on subject vehicles equipped with panoramic sunroofs. Over time, the subject panels may exhibit cosmetic degradation leading to replacement of the panel, a procedure which entails: removal of the old panel and adhesive, site preparation, and installation of a replacement panel with new adhesive.The consumer complaints that prompted the opening of PE21-001 all described detachments of front roof panels that had been replaced after the vehicle was put into service.Mercedes' internal investigation identified a broader scope of affected vehicles (2014-2020 CLA, GLA, C, S, GLC, and GLE class) and found the following potential service procedure- related causes of front roof panel detachments:- Improper surface pretreatments such as the use of the wrong primer or cleaner or scoring of the surface; or - Use of the incorrect adhesive.These conditions lead to a front roof panel bond that, even if sound at the time of repair, cannot maintain its strength over time and environmental exposure.Mercedes updated its service and parts ordering systems to reinforce the proper use of specified kits and procedures via webinars, shop foreman meetings, and explicit reference to the risks incurred by diverging from the repair procedures. Mercedes is also furnishing parts ordering assistance, and will hold dealerships accountable for improper repairs.ODI's analysis of the ten complaints it has received from the public (VOQ's) and MBUSA's complaint data submitted in response to the information request letter for PE21-001 identified a total of 57 non-duplicative reports alleging incidents in which the front roof panel detached from the vehicle while in motion. Included within the 57 reports are incidents where consumers state the panel detached ...and flew off into traffic.On March 19, 2021, Mercedes notified NHTSA that it would recall subject vehicles with front roof panels known to have been replaced after the original sale of the vehicle. In total, the recall (designated as Recall 21V197) covers 15,099 vehicles that were ever registered in the United States. Based on Recall 21V197 and the remedy implemented by Mercedes, further investigation does not appear to be warranted at this time.Accordingly, this investigation is closed.The ODI complaints cited above can be viewed at www.nhtsa.gov under the following ODI identification numbers: 11376425, 11352686, 11351629, 11349158, 11341541, 11337594, 11324100, 11311591, 11222127, 11404183

STRUCTURE:BODY:ROOF AND PILLARSLed to recall 21V197000

Recent owner complaints

Reports submitted to NHTSA, shown in the owner's own words

Body & structure
Filed Aug 8, 2025

The contact owns a 2015 Mercedes Benz C400. The contact stated that while vehicle was inside a high-pressure car wash, water leaked from the roof panel at the front of the vehicle, nearby the front windshield. The cause of the failure was not yet determined, and the vehicle was not repaired. The manufacturer was notified of the failure, but no assistance was offered. The contact was informed that the VIN was not included in the NHTSA Campaign Number: 23V854000 (STRUCTURE). The contact stated that the vehicle had experienced the failure listed in the recall. The local dealer was not contacted. The failure mileage was 100,000.

NHTSA ID
11679248
Incident
Feb 8, 2025
Mileage
100,000 mi
Suspension
Filed Feb 10, 2025

Rear subframe cracked while driving and rear of car sways from one lane to the next when brakes are applied. Car is not safe

NHTSA ID
11641763
Incident
Jan 1, 2025
Body & structure
Filed Nov 1, 2024

The contact owns a 2015 Mercedes-Benz C400. The contact stated that while the vehicle was being serviced, the contact was informed by the dealer that the rear subframe needed to be replaced. The vehicle was not diagnosed or repaired. The manufacturer was notified of the failure. The failure mileage was 112,000.

NHTSA ID
11623121
Incident
Oct 31, 2024
Mileage
112,000 mi
Body & structure
Filed Aug 9, 2024

The contact owns a 2015 Mercedes-Benz C400. The contact stated while driving 55-60 MPH, the front roof panel separated and flew off. The contact drove back and was able to pick the front roof panel off the road. The vehicle was taken to the dealer, where it was determined that the front roof panel needed to be replaced. Additionally, the dealer informed the contact that the recall repair of NHTSA Campaign Number: 21V197000(Structure) was previously performed on the vehicle, and the additional related repair would be at the contact's expense. The vehicle was not repaired. The contact related the failure to NHTSA Campaign Number: 23V854000(Structure). The manufacturer was not notified of the failure. The failure mileage was approximately 74,000.

NHTSA ID
11607566
Incident
Aug 9, 2024
Mileage
74,000 mi
Body & structure
Filed Jun 23, 2024

My boyfriend and I were driving my 2015 MB C400 down the road in November 2020 and it was a beautiful day out so we decided we would open the sunroof to get some fresh air. I was driving so my boyfriend pressed the button for the sunroof to open. As the sunroof was opening, there was a cracking and popping sound coming from above us. We immediately pulled over at a gas station to see what was happening. Upon getting out of the car and looking closer at the sunroof, we noticed many cheap plastic components that were just broken and crumbled laying inside the sunroof tract. We removed the broken pieces and then tried to close the sunroof several times. T Each time, the sunroof went into the closed position BUT immediately went straight back to the popped up position and would not completely close again. I took my car to the MB dealership in Athens, Ga where they told me it would be almost $2500 to repair which I did not feel as if I should be held responsible for as I had just purchased the car in January 2020 only 11 months earlier. I was in fear that the sunroof would detach from the car and cause serious injury to any motorist behind me. I also have a [XXX] son who is now scared to ride in my car!! After doing much research on this issue, I have found that this is truly a common problem with this MB model. I have reached out to the corporate office a few times and they only tell me that there is no active recalls with my cars VIN. It is completely unacceptable that MB is fully aware of this issue yet they continue to disregard the potential harm to other motorists. Please help!!! INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID
11595949
Incident
Nov 15, 2020
Body & structure
Filed Feb 7, 2024

My car failed PA State inspection due to a hole and rusted rear subframe. I have determined that there is a recall associated with this issue but that my vehicle just missed the recall limit. The recall affected 2008-2015 models (C Class with chassis 204). My vehicle is a 2015 C Class with chassis 205. It is evident that my vehicle has the same structural/construction defects as the previous years and should have been included in this recall. I have provided photographic evidence (attached/uploaded below). This is a very expensive repair that I should not have to pay for. Please review and consider having this included in the recall process so that I can be reimbursed for this costly repair as it is the result of a faulty construction process. Thank you. Sincerely, [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID
11570624
Incident
Feb 7, 2024
Body & structure
Filed 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.

NHTSA ID
11431700
Incident
Aug 27, 2021
Engine
Filed Sep 5, 2017

ENGINE RANDOMLY STALLS AFTER SITTING AT RED LIGHT/OR WHILE IN TRAFFIC. ALL WARNING/DASHBOARD LIGHTS COME ON AND YOU CAN ONLY START THE CAR BY PUTTING IT IN PARK, THEN PUSHING START. THE CAR HAS LESS THAN 10K MILES. DEALERSHIP CAN'T FIND CODE OR REPLICATE THE ISSUE. INTERNET SEARCHES INDICATE IT IS AN ISSUE AND OTHER MAKES AND MODELS HAVE BEEN RECALLED, BUT WITHOUT A CODE THE DEALERSHIP DOESN'T KNOW WHAT TO DO. I WAS NEARLY REAR-ENDED BECAUSE IT DOESN'T HAPPEN UNTIL YOU TAKE YOUR FOOT OFF THE BRAKE AND PRESS THE GAS TO MOVE FORWARD, AND THAT'S WHEN THE ENGINE SHUTS OFF COMPLETELY. THIS HAPPENS RANDOMLY AND HAS HAPPENED SEVERAL TIMES.

NHTSA ID
11021610
Incident
Aug 29, 2017
Mileage
9,700 mi

Manufacturer communications

A bulletin sent by a manufacturer to its dealers. Not a recall, and repairs are not necessarily free.

LI46.35-P-067339

STEERING

Complaint During part of the steering movement, it feels heavier or more difficult to steer in the same spot every time. OR Rattling, humming, dry sliding/gravel noise from the electric steering system when steering (see attachment). Complaint does not impact the ability to safely steer or control the vehicle. Cause Ball screw drive (KGT) of electric steering damaged by: 1. External force due to: ‑ Hitting the curb/posts with the front wheels. ‑ Driving over obstacles (e.g. pothole/ threshold/ speed bump/ gully) at an inappropriate speed. 2. Corrosion/ water ingress through a damaged boot (see attachment). ‑ Cracks (1) ‑ High pressure cleaner (2) ‑ Animal bite (3) See various examples listed in the attachments for examples of outside influence. Remedy Remove boot clamps closest to steering gear housing on both left and right (as seen in "Steering Rack Boot Clamp Location"). Pull back boot and inspect for rust, broken end stops, water, or any other anomalies. Replace electric steering. Note: Steering gears replaced due to outside influence or damage must not be claimed under warranty!

LI72.20-P-075746

ELECTRICAL SYSTEM; STRUCTURE:BODY

Complaint Tailgate opens unintentionally. Cause Accidental or unnoticed activation of the button to open the tailgate on the vehicle key. EXAMPLE: when stored in trouser pocket, handbag etc. Remedy As of the 6th generation, the vehicle key can be recoded so that the tailgate no longer opens as a result of a long press on the button, but by double‑clicking on the button instead. This reduces the likelihood of the button being activated accidentally or unintentionally. The recoding can be carried out as follows: 1. Add SA Code O19 into VeDoc (O for Oscar, not "zero") • an XSS ticket may be necessary to add the SA code 2. Perform SCN coding of EIS N73 control unit 3. Deactivate the vehicle key (a successful deactivation is indicated by the LED lighting up 2x briefly and then 1x for a long period). 4. Place the vehicle key in the storage compartment on the key symbol and turn on the ignition. IMPORTANT: all other vehicle keys must be outside the recognition range of the vehicle when doing this! Perform steps 3 and 4 successively for all vehicle keys. Notes: 6th, 7th and 8th generation keys can be deactivated as follows: Up to modification year 22/1 by double clicking the "Lock button" As of modification year 22/1, by press and holding the “Lock button", then double‑click the “Unlock button" at the same time. On model series 167, the storage compartment with the key symbol is located in the armrest. The SCN coding from the EZS is only transferred correctly to the vehicle key under the following conditions: Only one vehicle key is located in the vehicle, this key has been deactivated and it is positioned on the marking in the storage compartment for the data transfer. The costs for this adaptation are to be borne by the customer. For the newer BR 174, 178, 244, 248, 520, and 540, a software update must be initiated, as there is no way to perform SCN coding.

LI54.65-P-080132

ELECTRICAL SYSTEM

Complaint 1. General Diagnostic Tips 2. One or More PARK Sensor Activations 3. Red Ring Around Vehicle 4. "Active Parking and Parking Assist Inoperative" on Instrument Cluster 5. Cameras 6. Other Park Topics. Cause Various root causes Remedy See attached diagnostic guide.

LI82.85-P-079087

ELECTRICAL SYSTEM

Complaint A popup is seen on the HU with the message "data connection temporarily not available". Potentially affected functionalities in NTG4.5, NTG5 1.Weather 2.Local Search 3.IP Radio 4.Send2Car 5.Speech Detection Service 6.Navigation 7.iHeartRadio 8.Traffic Cams Cause MB Apps is sundowned for all vehicles with NTG4.5 and NTG5 Head Unit Variant. Remedy No support available for NTG4.5 and NTG5 Head Unit Variants for MB App related topics. Note: Please do not create TIPS. Please do not replace any components. HU/Hermes SW update / SCN coding will not fix the issue.

LI82.62-P-078631

STRUCTURE:BODY

Complaint Clanking noise from the area of the speakers in the doors. Cause Under analysis. Remedy To narrow down the cause, first of all remove the door trim. • If the noise continues to occur even with the door trim removed, then continue the diagnosis working towards the speaker and if necessary, create a TIPS case with an informative video as an attachment. Information: Please refer to this document in the warranty claim and, after completing diagnosis, select the damage code corresponding to the component part that caused the problem. • If the noise stops when the door trim is removed, please proceed in accordance with LI72.10-P-067691. Information: In this case, do not use a damage code for the speakers in the warranty claim!

LI35.30-P-058566

POWER TRAIN

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).

Manufacturers file copies of the bulletins they send to dealers with NHTSA. These often describe diagnostic or repair procedures for a known condition. They are not recalls: repairs described in a bulletin are usually only free if the vehicle is still under warranty or the manufacturer has extended coverage.