2018 Mercedes Benz C 300 4matic problems, complaints & recalls
Most-reported problem areas: Structure:body:roof And Pillars (2) · Engine (2) · Visibility/Wiper (1)
Safety recalls (3)
Exterior Lighting:headlights 2018-12-19 · campaign 18V906000 · 2,364 vehicles
Defect: Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2018 Mercedes-Benz C300 and C300 4MATIC vehicles. The headlights on these vehicles may not be properly adjusted. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard (FMVSS) number 108, "Lamps, Reflective Devices, and Associated Equipment."
Risk: If the low beam headlight is not properly adjusted, the driver may have reduced visibility, increasing the risk of a crash.
Fix: MBUSA has notified owners, and dealers will inspect the setting of the headlights and adjust them, as necessary, free of charge. The recall began March 12, 2019. Owners may contact MBUSA customer service at 1-800-367-6372. MBUSA's number for this recall is 2019020008.
Air Bags:sensor:occupant Classification 2018-11-27 · campaign 18V838000 · 104,663 vehicles
Defect: Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2018 C300 Cabriolet, C300 Coupe, C300 4Matic Cabriolet, C300, C300 4Matic Coupe, C300 4Matic, C43 AMG Cabriolet, C43 AMG Coupe, C63 S AMG Cabriolet, C350e Plug-In Hybrid, C63 AMG Cabriolet, C63 AMG Coupe, C63 S AMG Coupe, C63 AMG, C63 S AMG, 2018-2019 GLC300 4Matic Coupe, GLC300, GLC63 AMG Coupe, GLC300 4Matic, GLC350e Plug-In Hybrid, GLC43 AMG Coupe, GLC43 AMG, GLC63 S AMG Coupe, and GLC63 AMG vehicles equipped with Audio 20 head units and aut
Risk: If the passenger air bag is incorrectly displayed as 'ON' when it is not, a front seat passenger may be unaware that the air bag will not deploy in the event of a crash, increasing their risk of injury.
Fix: MBUSA will notify owners, and dealers will update the audio head unit software, free of charge. The recall began January 3, 2019. Owners may contact MBUSA customer service at 1-800-367-6372. MBUSA's number for this recall is 2018120009.
Visibility:glass, Side/Rear 2018-09-11 · campaign 18V608000 · 387 vehicles
Defect: Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2018 Mercedes-Benz C300, C300 4MATIC, C63 AMG, and C63S AMG vehicles. Incorrect bonding of the rear window may cause the window to loosen and detach from the vehicle.
Risk: If the window detaches from the vehicle, it can become a road hazard, increasing the risk of a crash.
Fix: MBUSA will notify owners, and dealers will rework the rear window bonding, free of charge. The recall is expected to begin November 2, 2018. Owners may contact MBUSA customer service at 1-800-367-6372.
Service bulletins (141)
Technical service bulletins are repair instructions manufacturers send dealers for known issues. Unlike recalls, the fix is not automatically free — but naming the bulletin at the service desk can save diagnosis time and support goodwill repairs.
Steering 2026-09-26 · LI46.10-P-080896 · Service Bulletin/Repair Instructions
complaint slight creaking noises when steering. cause noises may come from one or more sleeves of the horn contact plate. remedy remove the horn contact plate and check the sleeves for noise; see attached video. if necessary, apply lubricant to the sleeves.
Power Train 2026-09-26 · LI27.00-P-073124 · Service Bulletin/Repair Instructions
complaint customer complaints relating to automatic transmission 725.0 (nag3 classic /9g‑tronic automatic transmission) and 725.1 (nag3 facelift/9g‑tronic automatic transmission facelift) for faster, more effective and more targeted diagnosis, intelligent predictive repair (ipr) has been developed a
Service Brakes 2026-09-22 · LI42.10-P-078779 · Service Bulletin/Repair Instructions
complaint repeat workshop visit for vehicle vibration while braking from 60mph. note: although the symptom is similar to a tire or wheel vibration, it is usually readily noticeable that it is distinctly different if it happens at all times or only while braking. cause although the cause of the vibra
Structure:body 2026-09-14 · LI82.62-P-078631 · Service Bulletin/Repair Instructions
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,
Power Train 2026-09-14 · LI27.10-P-075869 · Service Bulletin/Repair Instructions
complaint only vehicles with a variable transfer case are affected. this can be identified through control unit n45 or n15/7 in the quick test. when accelerating with light load, vibrations or jolting sensation may come from the drivetrain. it may be mistaken for a harsh shift. cause modified oil qu
Power Train 2026-09-04 · LI27.00-P-073124 · Service Bulletin/Repair Instructions
complaint customer complaints relating to automatic transmission 725.0 (nag3 classic / 9g‑tronic automatic transmission) and 725.1 (nag3 facelift/9g‑tronic automatic transmission facelift) for faster, more effective and more targeted diagnosis, intelligent predictive repair (ipr) has been developed
Showing the 6 most recent of 141 bulletins. Search all of them free at nhtsa.gov.
What owners report
2026-08-28 · Unknown Or Other“sunroof causing dangerous pinch conditions. roof tracks break and cause pinch areas with partial opening of roof …”
2026-07-30 · Visibility/Wiper“i have begun noticing symptoms of the adhesive failing, such as excessive wind noise coming from the front roof area and visible gaps/separation between the panel and the vehicle body. this poses a severe safety risk, as the panel could completely detach while driving and become a high-speed road hazard. no warning lights have appeared. the vehicle…”
2026-07-24 · Unknown Or Other“2018 mercedes c300 - a hole rusted through the rear subframe causing structural safety concerns. this car has been routinely washed weekly and the frame should not have rusted through within only 8 years. this also led to a large repair bill.…”
2026-06-10 · Structure:body:roof And Pillars“****please force merces to recall all vin's!******* nhtsa id number: 23v854000 1) front glass roof panel came off while driving the car on the freeway. i didn't see or hear anything. when i got out of the car, i saw the entire piece has come off. this has caused my sunroof to malfunction, and it won't close now. i garage my car and barely drive it…”
2026-05-22 · Structure:body:roof And Pillars“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…”
2026-04-24 · Unknown Or Other“when i decelerate my brake lights don’t flash to warn the driver behind me that i am potentially slowing down .…”
2025-01-23 · Seat Belts · 59,000 mi“the contact owns a 2018 mercedes-benz c300 4matic. the contact stated that the front passenger's and driver's side seat belts had failed to retract and return to the stowed position. the contact related the failure to nhtsa campaign number: 21v032000 (seat belts); however, the vin was not included. the dealer was notified of the failure and informe…”
2024-09-09 · Steering“car has less than 34,000 miles on it. one day went to drive and the vehicle wouldn't turn and an error message popped up "power steering malfunction, check owners manual" had it towed to dealer and they said they couldn't find anything wrong with it. according to the dealer, no sign of wear and tear, no physical damage, …”
2024-04-23 · Engine“very common problem on all mercedes - code p052e - second time on this car. engine light, 2nd time on this car. car is 2018 and has 45k miles. first time it was at 28037 miles. this is a major issue costing consumers $1500-$2500 to repair and needs a recall from manufacturer…”
2023-01-24 · Engine“2018 mercedes c300. p052e check engine code. positive crankcase ventilation failed with less than 28k miles. common reported problem but not covered after warranty period, even with extended warranty addition. it's a major part of the engine function and 6 hours of labor to replace. mercedes benz should cover this type of fault on the design.…”
Excerpts of consumer complaints filed with NHTSA, lightly truncated. They are owner statements, not verified findings.