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2014 Mercedes-Benz S400

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By Research the Car 3 min read

The 2014 Mercedes-Benz S400 Hybrid is a luxury sedan offering a blend of performance and efficiency. The S400 Hybrid features a 3.5-liter V6 engine paired with an electric motor, producing a combined 302 horsepower and 273 lb-ft of torque. While lauded for its smooth ride, opulent interior, and advanced technology, some owners have reported encountering specific issues. Potential downsides include higher maintenance costs associated with its complex hybrid system and the potential for certain electrical or electronic glitches. The other engine options available for the 2014 S-Class are a 4.7L V8 (S550), a 6.0L V12 (S600), and a 5.5L V8 (S63 AMG). All engines are paired with a 7-speed automatic transmission, with the exception of the S600, which comes with a 5-speed automatic.

Electric Motor

3.5L V6 Hybrid Motor

  • Hybrid Battery Failure
    • Description/Symptoms: Reduced fuel economy, warning lights on the dashboard related to the hybrid system, decreased performance, or complete failure of the hybrid system.
    • Solution: Replacement of the hybrid battery pack.
    • Estimated Cost to Fix: $8,000 - $15,000+
    • Recalls: None Found
  • Electric Motor Malfunction
    • Description/Symptoms: Jerky acceleration, loss of electric assist, error messages related to the electric motor.
    • Solution: Diagnosis and repair/replacement of the electric motor or associated components (inverter, control module).
    • Estimated Cost to Fix: $2,000 - $7,000+
    • Recalls: None Found

Transmission

7-Speed Automatic (7G-Tronic)

  • Harsh Shifting
    • Description/Symptoms: Rough or jerky gear changes, particularly during acceleration or deceleration.
    • Solution: Transmission fluid flush, software update, or valve body replacement.
    • Estimated Cost to Fix: $300 - $2,500+
    • Recalls: None Found
  • Torque Converter Issues
    • Description/Symptoms: Shuddering at low speeds, especially during light acceleration, or a complete failure of the torque converter.
    • Solution: Replacement of the torque converter.
    • Estimated Cost to Fix: $1,500 - $3,500+
    • Recalls: None Found

Suspension

  • Airmatic Suspension Failure
    • Description/Symptoms: Sagging suspension (especially overnight), uneven ride height, warning lights related to the suspension system, and a bumpy or uncomfortable ride.
    • Solution: Replacement of air struts, air compressor, or valve block.
    • Estimated Cost to Fix: $1,000 - $4,000+ per component.
    • Recalls: None Found
  • Air Leak
    • Description/Symptoms: Hissing sound from one or more corners of the vehicle, noticeable drop in ride height on one or more corners.
    • Solution: Replacement of the leaking air strut or air line.
    • Estimated Cost to Fix: $800 - $2,500+
    • Recalls: None Found

Electrical

  • COMAND System Malfunctions
    • Description/Symptoms: Freezing, slow response, display issues, navigation problems, or complete failure of the infotainment system.
    • Solution: Software update, replacement of the COMAND unit.
    • Estimated Cost to Fix: $500 - $3,000+
    • Recalls: None Found
  • Sensor Failures (Parking Sensors, Blind Spot Monitoring)
    • Description/Symptoms: Erratic behavior of the affected system, false alarms, or complete system failure.
    • Solution: Replacement of the faulty sensor(s).
    • Estimated Cost to Fix: $200 - $800+ per sensor
    • Recalls: None Found
  • Battery Drain
    • Description/Symptoms: Car battery dies frequently, even after short periods of inactivity.
    • Solution: Diagnose and repair parasitic drain (faulty module, wiring issue).
    • Estimated Cost to Fix: $150 - $1,000+
    • Recalls: None Found

Interior

  • Sunroof Issues
    • Description/Symptoms: Sunroof fails to open or close properly, makes excessive noise, or leaks.
    • Solution: Repair or replacement of the sunroof motor, tracks, or seals.
    • Estimated Cost to Fix: $300 - $1,500+
    • Recalls: None Found
  • Seat Motor Failure
    • Description/Symptoms: Seat is stuck in one position, or the seat motor makes noise but doesn’t move the seat.
    • Solution: Replacement of the seat motor or associated components.
    • Estimated Cost to Fix: $400 - $1,200+
    • Recalls: None Found

Exterior

  • Headlight Malfunctions (LED Headlights)
    • Description/Symptoms: Flickering, dimming, or complete failure of the LED headlights.
    • Solution: Replacement of the headlight assembly or control module.
    • Estimated Cost to Fix: $1,000 - $4,000+ per headlight
    • Recalls: None Found
  • Door Lock Actuator Failure
    • Description/Symptoms: Door will not lock or unlock using the remote or interior switch.
    • Solution: Replacement of the door lock actuator.
    • Estimated Cost to Fix: $300 - $800+
    • Recalls: None Found

Summary:

The 2014 Mercedes-Benz S400 Hybrid, while offering a luxurious driving experience, presents owners with potential issues, particularly related to its hybrid system and advanced electronics. Problems with the hybrid battery and electric motor can be very expensive to fix. Suspension and electrical issues are also common, but these problems are not extremely common and can sometimes be fixed with a reset. The transmission and suspension systems are also prone to failures that may result in costly repairs.

Mercedes-Benz, S400
Mercedes-Benz S400 2014
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