2009 Mercedes-Benz CL500

2009 Mercedes-Benz CL500

Overview

The 2009 Mercedes-Benz CL500, a luxury grand tourer, is known for its sophisticated engineering and powerful performance. While generally well-regarded for its build quality and comfort, like any complex vehicle, it has specific areas where owners have reported issues. This analysis focuses on documented technical reliability concerns beyond routine maintenance, providing insights into potential problem areas for prospective buyers or current owners. The CL500’s advanced systems, while offering a premium experience, can also be sources of more significant repair needs.

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Engine

5.5L V8 (M273)

Intake Manifold Runner Flap Actuator Failure

• Symptoms: Check engine light, rough idle, loss of power, rattling noise from intake.
• Solution: Replacement of the intake manifold or actuator.
• Cost: $500 - $1200

Timing Chain Wear

• Symptoms: Rattling noise from the front of the engine, especially on startup; check engine light.
• Solution: Replacement of timing chain, tensioners, and guides.
• Cost: $1500 - $3000

Transmission

7G-TRONIC (7-Speed Automatic)

Torque Converter Issues

• Symptoms: Shuddering during acceleration, slipping gears, delayed engagement.
• Solution: Rebuild or replacement of the torque converter.
• Cost: $1000 - $2500

Valve Body Malfunction

• Symptoms: Harsh shifting, transmission fault warnings, inability to select gears.
• Solution: Repair or replacement of the valve body.
• Cost: $800 - $2000

Suspension

Active Body Control (ABC)

Hydraulic Leaks

• Symptoms: Vehicle sagging, suspension warning lights, fluid leaks under the car.
• Solution: Repair or replacement of leaking hoses, struts, or pump.
• Cost: $1000 - $4000+

ABC Pump Failure

• Symptoms: Loss of hydraulic pressure, suspension dropping, loud whining noise from pump.
• Solution: Replacement of the ABC hydraulic pump.
• Cost: $800 - $1500

Electrical

General Electrical System

SAM (Signal Acquisition Module) Failure

• Symptoms: Various warning lights, malfunctioning interior/exterior lights, power window issues.
• Solution: Diagnosis and potential replacement of the SAM unit.
• Cost: $500 - $1500

Keyless Go System Malfunctions

• Symptoms: Difficulty starting the car, door handle sensors not working, key fob recognition issues.
• Solution: Diagnosis and repair/replacement of related sensors or control modules.
• Cost: $300 - $1000

Exterior

Standard Exterior

No Major Issues

• Symptoms: No widespread issues reported.
• Solution: No widespread issues reported.
• Cost: N/A

Interior

General Interior

Seat Control Malfunctions

• Symptoms: Power seats not adjusting, memory functions failing.
• Solution: Repair or replacement of seat control modules or motors.
• Cost: $300 - $800

Headliner Sagging

• Symptoms: Fabric detaching from the headliner board, especially in warmer climates.
• Solution: Re-gluing or replacement of the headliner.
• Cost: $400 - $900

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Summary Verdict

The 2009 Mercedes-Benz CL500 offers a luxurious and powerful driving experience, but potential owners should be aware of its specific reliability concerns. The Active Body Control (ABC) suspension is a notable area for potential costly repairs due to hydraulic leaks and pump failures. The 5.5L V8 engine can experience issues with the intake manifold runner flap actuator and timing chain wear. The 7G-TRONIC transmission may develop problems with the torque converter or valve body. Electrical gremlins, particularly with the SAM module and Keyless Go system, are also reported. While the exterior is generally robust, interior components like seat controls and headliners can degrade over time. Regular, thorough inspections and a willingness to address these potential issues are crucial for maintaining this high-end coupe.