2003 Mercedes-Benz CL600

The 2003 Mercedes-Benz CL600 is a luxurious grand touring coupe known for its powerful engine and opulent features. The CL600 came standard with a 5.5L V12 engine producing 493 horsepower and 590 lb-ft of torque. Other engine options available for the 2003 CL-Class included a 5.0L V8 in the CL500 and a supercharged 5.4L V8 in the CL55 AMG. All engines were paired with a 5-speed automatic transmission. Owners often praise the CL600 for its smooth ride, powerful acceleration, and luxurious interior. However, common complaints include high maintenance costs, complex electronics, and potential reliability issues related to the car’s age and sophisticated systems.

Engine

5.5L V12 (M275)

• Coil Pack Failure
  • Description/Symptoms: Engine misfires, rough running, 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: ABC warning light, suspension malfunctions, car lowering, leaking fluid. While directly related to the suspension, the ABC system is often powered by an engine-driven pump and its failure can severely impact engine performance and drivability.
  • Solution: Replace the ABC pump and flush the hydraulic system.
  • Estimated Cost to Fix: $1,500 - $3,000+
  • Recalls: None Found
• Oil Leaks
  • Description/Symptoms: Visible oil leaks on the engine, burning oil smell, low oil level. Common leak locations include valve cover gaskets and the rear main seal.
  • Solution: Replace the leaking gaskets or seals.
  • Estimated Cost to Fix: $300 - $1,500+, depending on the location of the leak.
  • Recalls: None Found

Transmission

5-Speed Automatic (722.6)

• Torque Converter Failure
  • Description/Symptoms: Shuddering or vibration at low speeds, especially during light acceleration.
  • Solution: Replace the torque converter.
  • Estimated Cost to Fix: $1,200 - $2,500+
  • Recalls: None Found
• Valve Body Issues
  • Description/Symptoms: Harsh or erratic shifting, delayed engagement, slipping between gears.
  • Solution: Replace or rebuild the valve body.
  • Estimated Cost to Fix: $800 - $2,000+
  • Recalls: None Found

Suspension

• ABC (Active Body Control) Strut Failure
  • Description/Symptoms: Car leaning to one side, uneven ride height, ABC warning light, knocking noises.
  • Solution: Replace the faulty ABC strut(s).
  • Estimated Cost to Fix: $1,500 - $3,000+ per strut.
  • Recalls: None Found
• ABC System Hose Leaks
  • Description/Symptoms: Fluid leaks near the struts or pump, suspension malfunctions, ABC warning lights.
  • Solution: Replace the leaking hoses.
  • Estimated Cost to Fix: $300 - $1,000+, depending on the hose location.
  • Recalls: None Found

Electrical

• Battery Drain
  • Description/Symptoms: Car won’t start after sitting for a short time, frequent jump starts, dead battery.
  • Solution: Diagnose and repair the parasitic drain. Common causes include faulty modules, alarm system issues, or aftermarket electronics.
  • Estimated Cost to Fix: $100 - $1,000+, depending on the source of the drain.
  • Recalls: None Found
• SAM (Signal Acquisition Module) Failure
  • Description/Symptoms: Malfunctioning lights, wipers, windows, or other electrical components. The SAM module controls various electrical functions throughout the car.
  • Solution: Replace the faulty SAM module.
  • Estimated Cost to Fix: $500 - $1,500+
  • Recalls: None Found

Exterior

• Rust
  • Description/Symptoms: Rust forming on fenders, door panels, rocker panels, or other body areas.
  • Solution: Repair or replace rusted panels.
  • Estimated Cost to Fix: $500 - $5,000+, depending on severity and location.
  • Recalls: None Found

Interior

• Headliner Sagging
  • Description/Symptoms: The fabric headliner detaching from the roof.
  • Solution: Replace or repair the headliner.
  • Estimated Cost to Fix: $300 - $800+
  • Recalls: None Found
• Pixelated Instrument Cluster Display
  • Description/Symptoms: Pixels missing or faded on the instrument cluster display, making it difficult to read information.
  • Solution: Replace or repair the instrument cluster.
  • Estimated Cost to Fix: $500 - $1,500+
  • Recalls: None Found

Summary

The 2003 Mercedes-Benz CL600, while a luxurious and powerful vehicle, is known for its potential reliability issues, particularly related to its complex systems like the ABC suspension and electrical components. Engine and transmission issues, while less frequent, can also be costly to repair. Addressing these common problems can be expensive, with repair costs ranging from a few hundred to several thousand dollars depending on the specific issue. Potential buyers should be aware of these potential expenses before purchasing a used CL600.