2009 Mercedes-Benz SL65 AMG

2009 Mercedes-Benz SL65 AMG

Overview

The 2009 Mercedes-Benz SL65 AMG, a high-performance roadster, is known for its potent V12 engine and luxurious features. While generally well-engineered, like any complex performance vehicle, it can experience specific issues related to its advanced systems. Owners should be aware of potential concerns primarily centered around the powertrain, particularly the twin-turbocharged V12 engine and its associated systems, as well as the sophisticated electronics that manage its performance and comfort. Regular and specialized maintenance is crucial for mitigating these potential problems and ensuring the longevity of this exotic machine. The SL65 AMG represents a significant investment, and understanding its common reliability points is key for prospective and current owners.

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Engine

6.0L Twin-Turbo V12 (M275)

Turbocharger Failure

• Symptoms: Loss of power, excessive smoke, whistling noises from the engine bay.
• Solution: Replacement of turbochargers.
• Cost: $3,000 - $7,000

Intercooler Leaks

• Symptoms: Reduced engine performance, overheating, coolant smell.
• Solution: Repair or replacement of intercooler hoses and components.
• Cost: $500 - $1,500

Ignition Coil Failure

• Symptoms: Misfires, rough idling, check engine light.
• Solution: Replacement of faulty ignition coils.
• Cost: $200 - $500 per coil

Coolant Leaks (ABC System Related)

• Symptoms: Low coolant level, visible leaks, engine overheating.
• Solution: Diagnosis and repair of leaks, often related to the Active Body Control (ABC) system’s integration with the engine cooling.
• Cost: $800 - $2,500

Transmission

5-Speed Automatic (722.6)

Transmission Control Module (TCM) Failure

• Symptoms: Erratic shifting, transmission slipping, ‘limp mode’.
• Solution: Replacement of the TCM.
• Cost: $1,000 - $2,500

Torque Converter Issues

• Symptoms: Shuddering during acceleration, slipping, delayed engagement.
• Solution: Replacement of the torque converter.
• Cost: $1,500 - $3,000

Suspension

Active Body Control (ABC)

Hydraulic Leaks

• Symptoms: Vehicle sagging, ‘ABC Malfunction’ warning on the dashboard, stiff ride.
• Solution: Repair or replacement of hydraulic lines, pumps, or struts.
• Cost: $1,500 - $5,000+

ABC Pump Failure

• Symptoms: Loss of hydraulic pressure, vehicle sagging, loud whining noise from the pump.
• Solution: Replacement of the ABC hydraulic pump.
• Cost: $1,000 - $2,500

Electrical

Infotainment System

COMAND System Glitches

• Symptoms: Screen freezing, unresponsive buttons, audio issues, navigation problems.
• Solution: Software updates or replacement of the COMAND head unit.
• Cost: $500 - $2,000

Sensors (e.g., Parking Sensors, ABS Sensors)

Sensor Malfunctions

• Symptoms: False warnings, system failures (e.g., parking assist not working, ABS light on).
• Solution: Replacement of faulty sensors.
• Cost: $200 - $600 per sensor

Exterior

Retractable Hardtop Mechanism

Actuator/Motor Failure

• Symptoms: Top not opening or closing properly, unusual noises during operation.
• Solution: Repair or replacement of roof actuators, motors, or hydraulic components.
• Cost: $1,000 - $3,000

Seal Wear

• Symptoms: Water leaks into the cabin, wind noise.
• Solution: Replacement of weather stripping and seals.
• Cost: $300 - $800

Interior

Climate Control System

Blower Motor Resistor Failure

• Symptoms: Fan only works on highest setting or not at all.
• Solution: Replacement of the blower motor resistor.
• Cost: $150 - $300

Seat Adjustment Motors

Malfunctioning Seat Adjustments

• Symptoms: Power seats not moving or moving erratically.
• Solution: Replacement of seat adjustment motors or control modules.
• Cost: $400 - $1,000 per seat

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Summary Verdict

The 2009 Mercedes-Benz SL65 AMG is a formidable performance car with a complex V12 engine and advanced systems. While it offers exhilarating performance, potential owners should be prepared for higher maintenance and repair costs, particularly concerning the twin-turbo V12 engine, its cooling and turbo systems, and the sophisticated Active Body Control (ABC) suspension. Electrical gremlins, especially within the COMAND system, and issues with the retractable hardtop mechanism are also noted. Despite these potential challenges, with diligent maintenance and prompt attention to issues, the SL65 AMG can remain a rewarding exotic car. Reliability is significantly dependent on the quality of previous maintenance and the owner’s willingness to invest in specialized care.