The Mercedes-Benz S-Class W220 S 65 AMG is a masterpiece of engineering, combining unparalleled luxury with a high-performance V12 engine. Produced between 2003 and 2006, this model offered cutting-edge technology and opulence that defined the flagship S-Class series. However, despite its prestige, the W220 S 65 AMG is not without its challenges. Owners and enthusiasts often encounter specific issues, ranging from engine and transmission problems to electrical and suspension faults. In this comprehensive guide, we’ll delve into the common problems of the W220 S 65 AMG, explore their causes, and offer solutions.
Mercedes S-Class W220 S 65 AMG Engine Performance Issues
The S 65 AMG features a hand-built 6.0-liter bi-turbocharged V12 engine, delivering astonishing power and torque. However, this complex engine is prone to a range of issues that can impact its performance and reliability.
Oil leaks are a persistent problem in the W220 S 65 AMG, often caused by failing gaskets and seals. The valve cover gaskets, oil cooler seals, and rear main seal are common areas where leaks occur. These issues are exacerbated by the intense heat generated by the bi-turbo V12 engine, which accelerates the degradation of rubber components. Symptoms of oil leaks include visible oil puddles under the car, a burning oil smell, or a drop in oil levels. Fixing oil leaks involves identifying the affected area and replacing the damaged gaskets or seals. Using high-quality synthetic oil and regularly checking oil levels can help prevent future leaks.
Another common issue is turbocharger failure. The twin turbochargers are critical to the engine’s high-performance output but are prone to wear and damage over time. Symptoms of turbocharger failure include reduced power, excessive smoke from the exhaust, and unusual whining noises during acceleration. The causes often include oil contamination, inadequate lubrication, or excessive stress on the turbos. Replacing the faulty turbocharger is the only solution, and preventative measures include regular oil changes and using high-quality oil to ensure proper lubrication.
The ignition coil failure is another engine-related problem. The S 65 AMG’s V12 engine relies on multiple ignition coils to deliver consistent spark to each cylinder. Over time, these coils can fail, leading to misfires, rough idling, and reduced power. Heat and electrical wear are the primary culprits behind ignition coil failure. Replacing the faulty ignition coils and ensuring the spark plugs are in good condition can resolve this issue. Using OEM-quality parts and performing regular engine diagnostics can prevent premature ignition coil failure.
Mercedes S-Class W220 S 65 AMG Transmission Problems
The W220 S 65 AMG is equipped with the robust 5-speed automatic transmission (722.6), designed to handle the immense torque of the V12 engine. Despite its durability, this transmission is not immune to problems, especially as the vehicle ages.
A common complaint among owners is transmission slipping or delayed shifting. These issues often stem from a worn conductor plate, which houses critical sensors for the transmission. A failing conductor plate can cause erratic shifting, hesitation, or even the inability to engage gears. Old or contaminated transmission fluid can also contribute to these problems by causing internal wear. Resolving this issue typically involves replacing the conductor plate and performing a complete transmission fluid and filter change. Regular fluid changes using the manufacturer-recommended ATF can prevent premature wear and extend transmission life.
Another transmission-related issue is torque converter failure. The torque converter transfers power from the engine to the transmission, and its failure can result in shuddering during acceleration, poor fuel efficiency, or difficulty in shifting gears. Excessive heat, low fluid levels, or internal wear are common causes of torque converter failure. Replacing the torque converter is necessary to restore proper operation. Preventative measures include monitoring transmission fluid levels and ensuring adequate cooling to avoid overheating.
Mercedes S-Class W220 S 65 AMG Suspension Problems
The W220 S 65 AMG features the advanced Active Body Control (ABC) suspension system, which enhances ride comfort and handling. While this system provides a superior driving experience, it is also a source of frequent issues that can be costly to repair.
One of the most common problems is ABC pump failure. The hydraulic pump is responsible for maintaining the system’s pressure, allowing the suspension to adjust in real-time. When the pump fails, the suspension may sag, or the car may lean to one side. Warning messages such as “ABC Drive Carefully” often appear on the dashboard. Causes of pump failure include wear and tear, fluid leaks, or contamination in the hydraulic system. Replacing the pump is necessary to restore suspension functionality. Regularly checking and replacing the ABC fluid can help prevent pump failure.
Another common issue is leaking hydraulic struts. The struts in the ABC system are prone to developing leaks due to high-pressure operation and aging seals. Symptoms include uneven ride height, clunking noises, or a noticeable decline in ride quality. Replacing the leaking struts with high-quality aftermarket or OEM parts is the recommended solution. Routine inspections of the suspension system can catch early signs of leaks and prevent further damage.
The ABC control module is another potential weak point. This electronic module governs the suspension system and can fail due to software glitches or electrical faults. When the module malfunctions, the suspension may behave erratically or become unresponsive. Replacing or reprogramming the control module is often required to resolve these issues.
Mercedes S-Class W220 S 65 AMG Electrical Problems
The Mercedes S-Class W220 S 65 AMG is equipped with cutting-edge electronic systems, but these systems can also be a source of recurring problems. Electrical issues are often complex and require precise diagnostics to resolve. Two of the most common electrical concerns include battery drain and failures in the COMAND infotainment system.
Battery drain is a well-documented problem in the W220 S 65 AMG. Many owners report unexplained battery depletion, often leaving them stranded with a car that won’t start. This issue is usually caused by parasitic draws from malfunctioning components, such as control modules, relays, or the COMAND system. Faulty door locks and trunk latches that fail to close circuits properly can also contribute to this problem. Diagnosing battery drain involves systematically testing circuits to identify the source of the draw. Replacing or repairing the malfunctioning component typically resolves the issue. To prevent battery drain, ensure all interior lights and electronics are turned off when the car is parked, and have the electrical system checked regularly.
Failures in the COMAND infotainment system are another frequent complaint. This system controls navigation, audio, and various vehicle settings, and when it malfunctions, it can cause significant inconvenience. Common issues include frozen screens, unresponsive controls, or the system failing to turn on altogether. These problems are often caused by outdated software, failing control modules, or wiring faults. Updating the COMAND software or replacing the faulty module can restore functionality. Regular system updates and careful handling of the infotainment controls can help avoid such problems.
Mercedes S-Class W220 S 65 AMG Cooling System Problems
The cooling system in the W220 S 65 AMG is critical for maintaining the performance and longevity of the bi-turbocharged V12 engine. However, certain components in the system are prone to failure, which can lead to overheating and costly repairs.
Radiator leaks are a common problem. The radiator is responsible for dissipating heat from the engine coolant, but over time, it can develop cracks or corrosion, particularly in vehicles that haven’t undergone regular maintenance. Symptoms of radiator leaks include visible coolant pooling under the car, low coolant levels, or overheating. Corrosion from degraded coolant or physical damage from road debris are the primary causes of radiator leaks. Fixing this issue involves repairing minor leaks with a sealant or replacing the radiator if the damage is extensive. Regular coolant flushes and using high-quality, manufacturer-recommended coolant can prevent corrosion and prolong the radiator’s life.
Thermostat and water pump failures are also common in this model. The thermostat regulates coolant flow, while the water pump circulates coolant through the engine and radiator. A stuck thermostat or a failing water pump can cause the engine to overheat or operate inefficiently. Symptoms include fluctuating engine temperatures, coolant leaks, or a whining noise from the water pump. Replacing the faulty component is essential to restoring proper cooling system function. Regular inspections and maintenance can help identify early signs of wear and prevent overheating issues.
Mercedes S-Class W220 S 65 AMG Interior and Comfort Issues
The W220 S 65 AMG boasts a luxurious interior filled with advanced features, but some of these features are prone to failure as the car ages. Common issues include seat adjuster malfunctions and problems with the climate control system.
The power-adjustable seats are a hallmark of comfort in the W220, but they are also a source of frustration for many owners. Over time, the seat adjustment motors or switches can fail, leaving the seats stuck in one position. Moisture intrusion, wear on the motor, or faulty wiring are common causes of this issue. Replacing the faulty motor or switch often resolves the problem. To prevent future malfunctions, it’s important to keep the interior dry and avoid overusing the seat adjustment controls.
The climate control system, designed for dual-zone temperature management, can also develop faults. Common problems include inconsistent cooling or heating, weak airflow, or a complete failure of the system. These issues are often caused by a failing blower motor, clogged cabin air filters, or refrigerant leaks. Electrical faults in the climate control module can exacerbate these problems. Addressing these issues involves cleaning or replacing the filters, repairing the blower motor, and recharging the refrigerant. Regular maintenance, such as replacing filters and checking refrigerant levels, ensures the climate control system operates efficiently.
Mercedes S-Class W220 S 65 AMG Rust and Corrosion
Rust is a significant concern for the W220 S 65 AMG, particularly in regions with harsh winters or frequent road salt use. Rust commonly appears on the wheel arches, undercarriage, and along the edges of the doors and trunk. Left untreated, rust can spread and compromise the vehicle’s structural integrity.
The primary cause of rust is poor drainage design, which allows water and debris to accumulate in certain areas. Insufficient rust-proofing during manufacturing exacerbates the issue. Addressing rust involves sanding down the affected areas, applying rust inhibitors, and repainting to restore protection. Preventative measures include regular washing, especially in winter, and applying rust-proofing treatments to vulnerable areas.
Mercedes S-Class W220 S 65 AMG Active Body Control (ABC) System Failures
The advanced Active Body Control (ABC) suspension system is a defining feature of the S 65 AMG, providing exceptional ride quality and handling. However, this system is complex and prone to failures that can be both costly and challenging to repair.
The most common problem with the ABC system is hydraulic fluid leaks from the struts or hoses. These leaks can lead to a loss of pressure, causing the suspension to sag or become unresponsive. Warning messages, such as “ABC Drive Carefully,” are often displayed on the dashboard. Over time, the hydraulic pump can also fail due to excessive wear. Replacing leaking components or the hydraulic pump is necessary to restore proper suspension functionality. Regularly inspecting the system for leaks and maintaining fluid levels can help prevent ABC system failures.
Another frequent issue is failure of the ABC control module, which manages the system’s operations. A malfunctioning module can cause erratic suspension behavior or a complete system shutdown. Replacing or reprogramming the control module is often required to resolve these issues.
Conclusion
The Mercedes S-Class W220 S 65 AMG is an extraordinary vehicle that offers unparalleled luxury and performance, but it is not without its flaws. From engine and transmission issues to electrical, cooling, and suspension problems, understanding these common faults can help owners maintain their vehicles effectively. Regular maintenance, prompt repairs, and attention to detail are crucial for preserving the performance and reliability of this iconic model.
For expert diagnosis and repairs, visit European Auto Pro, 253 Goodwood Road, Kings Park, 5034 South Australia. Their experienced technicians specialize in Mercedes-Benz vehicles and are committed to keeping your S 65 AMG in peak condition.