2005 Mercedes-Benz S65 AMG

The 2005 Mercedes-Benz S65 AMG is a high-performance luxury sedan that boasts impressive power and features. It was offered with a single engine option, a 6.0L Twin-Turbo V12 producing 604 horsepower and 738 lb-ft of torque, paired with a 5-speed automatic transmission. Owners often praise its luxurious interior, smooth ride, and exceptional acceleration. Common complaints include high maintenance costs, complex electronics prone to failure, and the sheer size of the vehicle making it less nimble than smaller sports cars.

Engine

6.0L Twin-Turbo V12 (M275)

• Coil Pack Failure
  • Description/Symptoms: Rough idling, misfires, check engine light.
  • Solution: Replace faulty coil pack(s).
  • Estimated Cost to Fix: $200 - $400 per coil pack.
  • Recalls: None Found
• ABC (Active Body Control) Pump Failure
  • Description/Symptoms: Suspension warning lights, vehicle sagging, poor ride quality.
  • Solution: Replace ABC pump.
  • Estimated Cost to Fix: $1500 - $3000
  • Recalls: None Found
• Oil Leaks (Valve Cover Gaskets, Oil Cooler)
  • Description/Symptoms: Visible oil leaks, burning oil smell, low oil level.
  • Solution: Replace valve cover gaskets and/or oil cooler seals.
  • Estimated Cost to Fix: $500 - $1500
  • Recalls: None Found

Transmission

5-Speed Automatic (722.6)

• Conductor Plate Failure
  • Description/Symptoms: Erratic shifting, transmission stuck in gear, limp mode.
  • Solution: Replace conductor plate.
  • Estimated Cost to Fix: $800 - $1500
  • Recalls: None Found
• Torque Converter Failure
  • Description/Symptoms: Shuddering during acceleration, poor fuel economy, slipping transmission.
  • Solution: Replace torque converter.
  • Estimated Cost to Fix: $1500 - $3000
  • Recalls: None Found

Suspension

• ABC (Active Body Control) System Issues
  • Description/Symptoms: Vehicle sagging, uneven ride height, suspension warning lights. Accumulator spheres are a known weak point.
  • Solution: Diagnose and repair ABC system, replace accumulator spheres.
  • Estimated Cost to Fix: $500 - $3000+ depending on the component.
  • Recalls: None Found

Electrical

• EIS (Electronic Ignition Switch) Failure
  • Description/Symptoms: Key not recognized, vehicle unable to start.
  • Solution: Replace EIS module.
  • Estimated Cost to Fix: $1000 - $2000
  • Recalls: None Found
• SAM (Signal Acquisition Module) Failure
  • Description/Symptoms: Various electrical malfunctions, including lighting, wipers, and windows.
  • Solution: Replace faulty SAM unit.
  • Estimated Cost to Fix: $800 - $1500
  • Recalls: None Found
• Battery Drain
  • Description/Symptoms: Dead battery, needing frequent jump starts. Often caused by a faulty component not shutting down properly.
  • Solution: Diagnose and repair the source of the parasitic drain.
  • Estimated Cost to Fix: $200 - $1000+ depending on the complexity of the problem
  • Recalls: None Found

Exterior

• Rust (Especially Around Wheel Arches and Underbody)
  • Description/Symptoms: Visible rust on exterior panels.
  • Solution: Rust repair or panel replacement.
  • Estimated Cost to Fix: $500 - $5000+ depending on severity.
  • Recalls: None Found

Interior

• Air Conditioning Issues (Compressor, Actuators)
  • Description/Symptoms: Inconsistent cooling, failure to blow cold air, clicking noises from the dashboard.
  • Solution: Replace AC compressor or faulty actuators.
  • Estimated Cost to Fix: $500 - $2000+
  • Recalls: None Found
• Navigation System Failure
  • Description/Symptoms: Screen freezing, system not functioning.
  • Solution: Repair or replace the navigation unit.
  • Estimated Cost to Fix: $500 - $2000
  • Recalls: None Found
• Door Lock Actuator Failure
  • Description/Symptoms: Door won’t lock or unlock, unusual noises when locking/unlocking.
  • Solution: Replace the faulty door lock actuator.
  • Estimated Cost to Fix: $300 - $600 per door.
  • Recalls: None Found

Summary:

The 2005 Mercedes-Benz S65 AMG, while offering exceptional performance and luxury, is prone to several potentially expensive issues. Engine, transmission, suspension (especially the ABC system), and electrical problems are the most common areas of concern. Repair costs can range from a few hundred dollars for minor fixes to several thousand for major component replacements. The complex nature of the vehicle’s systems requires specialized diagnostic equipment and experienced technicians, further contributing to the overall cost of ownership. Potential buyers should be aware of these common issues and factor them into their purchase and maintenance budget.