2015 Mercedes-Benz C400

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.

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

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

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

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

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

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

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

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 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

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).

Dear Mercedes-Benz USA Dealers, The part numbers listed in the chart below should no longer be installed, and any existing stock must be returned to your facing PDC. The deadline for all dealer returns is no later than Thursday, July 9, 2026. After July 9th, returns of these parts will no longer be accepted. These parts should be returned via ZSR Special Return, using item category SCM Authorized Part Return. Please include a copy of this NCU as your authorization to return these parts. This procedure will not affect your return allowance. All returned parts will be replaced in accordance with the chart provided below.

Complaint Service code B1 displayed in the customer menu does not match the workshop code displayed in the workshop menu, e.g., 505 or 550A, which includes a service A. Cause The root cause is currently being investigated. Remedy To determine the cause, the instrument cluster control unit (N133/1) and powertrain control unit (N127) logs are required before confirming the service or correction using XENTRY Diagnosis. Please open a TIPS case to BCE inbox with the requested information in the attachments.

Complaint After successful commissioning of the HERMES control unit (N112/9) with XENTRY Diagnosis DVD 03/2026, the message "SOS - service not activated" appears on the instrument cluster. In addition, the following two conditions are also met: • HERMES (N112/9) control unit: event code B15CE00 is ACTIVE and STORED (A+S) • Vehicle Documentation System: For the HERMES control unit, the EID1, EID2, ICCID, IMEI, IMSI, TELNR fields in the "Identification/Serial number" column have the value "-" Cause Still under analysis Remedy Recommission the HERMES control unit (N112/9) with XENTRY Diagnosis 03/2026 and add-on 33399 installed or carry out the procedure with a newer version of XENTRY Diagnosis: XENTRY→ "N112/9 - Control unit for telematics services (HERMES)" -> "Adaptations" -> "Control unit commissioning" -> "Commissioning of previously installed control unit"

Complaint The customer requests deactivation of the N112/9 HERMES communication module Note: Deactivation of the HERMES control unit (N112/9) is not supported for gray-market vehicles. Cause Before deactivating the HERMES control unit (N112/9), it must be clarified by the legal department of the respective MPC whether and under what conditions deactivation may be carried out. If deactivation is not permissible under applicable law, the HERMES control unit (N112/9) must not be deactivated. Remedy Please inform the customer that, following deactivation, the vehicle will no longer be able to place an automatic emergency call, nor will the customer be able to place a manual emergency call. After deactivation, the Mercedes-Benz Digital Extras will also no longer be available. Please have the attached sample form checked by your market's legal department, adapted to local requirements if necessary, and approved. Furthermore, after informing the customer about the effects of deactivation, please have the workshop complete and sign the approved form together with the customer, and send it to the MPC via a TIPS case for audit-compliant documentation. Furthermore, the workshop must affix a sticker to the emergency call button cover on the overhead control panel and to the emergency call button itself. After affixing, pictures of the overhead control panel need to be attached to the TIPS case for audit-proof documentation. After deactivation, the HERMES control unit (N112/9) is in the "Out of Service" operating status, and the display "SOS NOT READY" appears in the Audio/COMAND system. This display message tells the customer that the emergency call function is not available. In detail, the following steps must be carried out 1. The workshop must inform the customer about the effects of deactivation (see above) 2. Legal review by the MPC Legal department to determine whether deactivation is permissible for the vehicle and provision of a market-specific customer form based on the examples (see "Example - Deactivation communication module HERMES customer declaration English V3.0.pdf") 3. Completion of the market-specific customer form by the workshop and obtaining the customer’s signature 4. Creation of a XSS ticket by the workshop for the MPC with the signed customer form attached 5. Written confirmation of legally reviewed and approved deactivation by the MPC in the TIPS case (see attachment How+to+request+adding+Code+09o+via+XSS+v2.pdf, point 1) 6. Creation of an XSS ticket for documentation of the SA code "09o" (zero nine oh) in the Vehicle Documentation System (see attachment How+to+request+adding+Code+09o+via+XSS+v2.pdf, steps 2–7) 7. Ordering of stickers (part number A9078172900), quantity: 2 8. Affixing of the sticker (part number A9078172900) to the cover of the emergency call button on the overhead control panel (see attachment HERMES-Deactivation_+pictures+of+sticker.png) 9. Affixing of the sticker (part number A9078172900) to the emergency call button on the overhead control panel (see attachment HERMES-Deactivation_+pictures+of+sticker.png) 10. Taking photos of the applied stickers and attaching them to the TIPS case 11. After the XSS ticket has been successfully processed, the communication module must be deactivated using XENTRY: • Connect XENTRY Diagnosis • Access the HERMES control unit (N112/9) • "Adaptation" tab, menu item "Teach-in processes" -> "Deactivation" • Follow the instructions

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).