2012 Mercedes-Benz S550

I purchased this vehicle in July 2020. I did a through check for recalls, warranty problems and could not identify any with this vehicle. From the get go the check engine light would come on. I checked the codes and they indicated an "electrical fault on bank 1, oxygen sensor 1. I replaced the wiring harness on that sensor as well as the sensor. From then until now the car would code weekly about the same issue. Eventually I started using a catalytic converter cleaner (it cleans off sulfur deposits) in an attempt to solve the issue. It would work for a couple of tanks of gas and then continuing coding. I asked MB on numerous occasions about what the issue was. They all said they had no idea. It looks to me like they knew what the issue was, but kept it to themselves. Several weeks ago I received a letter in the mail(not dated by postmark) but the letter was dated August, 2023. The letter outlined an issue with the catalytic converter system identifying my vehicle by vin. The same problem I have had all along. The letter came at a time when the car codes almost daily with the same issue as always, ONLY NOW THE VEHICLE STALLS occasionally while waiting at stop lights. I said great. I called to get an appointment to fix the issue only to be told that the fix window had passed. I told them that I just got the letter. They told me that the fix expired in December 2023. I called MB hotline at 1-800-367-6372 to see what was up. They said they would get back to me in 3 days. It's been a week so I called again and they advised me they can't help. It's an issue for the 2011, 2012, 2013, and 2014 MB S550 W221. Why is this not a recall and why won't they fix it. It's an expensive repair. They sent me the letter and said it was expired 6 months before I received the letter. Can you help?

NHTSA ID

11610863

Incident

Aug 26, 2024

There is a strong smell of fuel in the cabin. When I lifted up the rear seats, where the odor is coming from, I see a film of fuel around the fuel sending unit on the driver's side. I lift up the sound insulation and I see fuel that has leaked on total the top of the sending unit.

NHTSA ID

11469134

Incident

Jun 14, 2022

VEHICLE CUT ON FIRE WHILE SITTING LUCKY OUTSIDE, THE CORNER OF ENGINE PASSENGER SIDE BELLOW THE HEADLIGHT STORES THE SUSPENSION AIR PUMP AND ELECTRIC HYDRAULIC STEERING PUMP.. BASE ON MY INSPECTION THE EHPS HEATED AND SET ON FIRE.SOMEONE SAW THE CAR ON FIRE AND CALLED FIRE DEPT.. CAR WAS LOCK AND STORE AFTER HOURS

NHTSA ID

11413503

Incident

Apr 21, 2021

Mileage

22,300 mi

TL* THE CONTACT OWNS A 2012 MERCEDES-BENZ S550. WHILE THE VEHICLE WAS STATIONARY IN A PARKING LOT, THE CONTACT SMELLED FUEL FROM THE REAR OF THE VEHICLE. THERE WERE NO WARNING INDICATORS ILLUMINATED. ON SEPTEMBER 5, 2019, THE CONTACT WAS ALERTED BY SOMEONE OF A FUEL LEAK UNDER THE REAR OF THE VEHICLE. UPON INVESTIGATION, THE CONTACT ASSOCIATED THE FAILURE WITH NHTSA CAMPAIGN NUMBER: 12V557000 (FUEL SYSTEM, GASOLINE). THE CONTACT CALLED MERCEDES-BENZ OF ARROWHEAD (LOCATED AT 9260 W BELL RD, PEORIA, AZ 85382, (623) 815-3900) AND NOTIFIED THEM OF THE FAILURE. THE VEHICLE WAS NOT DIAGNOSED OR REPAIRED. THE MANUFACTURER WAS NOTIFIED OF THE FAILURE. THE FAILURE MILEAGE WAS 86,000.

NHTSA ID

11254246

Incident

Aug 30, 2019

Mileage

86,000 mi

THERE IS AN PLASTIC PLUG IN THE OIL SYSTEM THAT LEAKS OIL FROM THE ENGINE ON TO THE EXHAUST MANIFOLD. THIS WAS REPORTED BECAUSE OF INCREASED OIL CONSUMPTION, VAPOR IN THE ENGINE SPACE AND A SMELL OF BURNED OIL. THE PLASTIC PLUG IS KNOWN TO LEAK AND MERCEDES DOES NOTHING ABOUT THIS DURING WARRANTY AND INSTEAD WAITS UNTIL THE VEHICULAR IS OUT OF WARRANTY CAUSING AN INCREASED TIME FOR A FIRE POTENTIAL. THIS CAR IS DRIVEN ON CITY STREETS AND HIGHWAYS WITH THIS FIRE POTENTIAL.

NHTSA ID

11194863

Incident

Mar 31, 2019

Mileage

92,565 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).

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 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 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

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

Complaint Headlamps leaking or fogged Cause The fogging of the headlamp is a natural phenomenon which can occur under certain climatic conditions. In contrast to a leaky headlamp, physical fogging does not result in a technical impairment of the headlamp. A leak test must be performed to determine if physical fogging exists or if the headlamp is leaky. Remedy In advance, observe LI82.10-P-078301 "Headlamp/front fog lamp leaky or fogged". 1. Prepare headlamp/check for external damage: For headlamps with a closed system • Check the headlamps for any external damage and check also for correct seating of the Gore-diaphragm/correct latching of the cover caps. • If the headlamp exhibits any external damage, replace the headlamp. For headlamps with an open system • Check the headlamps for any external damage and seal off the vent then make sure the cover caps are latched correctly into place. • If the headlamp exhibits any external damage, replace the headlamp. Note: A headlamp with external damage is not a warranty or goodwill case. 2. Leak test of headlamp with overpressure: Connect test adapter to pressure tester. (Figure 1) Check test adapter for leak tightness. To do so, connect plug and coupling (Figure 2) and apply a maximum overpressure of 30 mbar. • The pressure must remain constant. If the pressure does not remain constant, use a new adapter. Seal all the outlet openings using sealing compound and the given diaphragm with the plunger (Figure 3). (Figure 4) • Make allowance for the different headlamp variants here (there are different outlet openings). Check if the headlamp needs to be removed to gain access to the diagnostic socket on the headlamp housing. Plug the adapter onto the diagnostic socket on the headlamp housing. (Figure 5). Apply a maximum of 30 mbar overpressure to the headlamp housing. Note: If the maximum overpressure of 50 mbar is exceeded the headlamp seal will be damaged. • If a pressure drop of less than 10 mbar is measured within 30 seconds, the headlamp is tight and there is natural physical condensation• If a higher pressure drop than 10 mbar is measured within 30 seconds, the headlamp is leaky. Note: The leaky position can be localized with the aid of soap suds. Replace any leaky headlamps. Desiccant packs can be installed for headlamps that are not leaky. Observe the following documents for installation of desiccant packs: • LI82.10-P-078302 Fogged headlamp, desiccant pack installed - open ventilation system • LI82.10-P-078304 Fogged headlamp, desiccant pack installed - closed ventilation system