General notes

If you cannot lock or unlock the vehicle with the SmartKey, either the battery in the SmartKey is discharged, the SmartKey is faulty or the starter battery is discharged.

replace it if necessary. Check the battery in the SmartKey and replace it if necessary.
mechanical key. Unlock the driver's door using the mechanical key.
Lock the vehicle.
contacts checked at a qualified specialist Have the starter battery and the battery contacts checked at a qualified specialist workshop.

If the SmartKey is faulty, contact Roadside Assistance or a qualified specialist workshop.

    See also:

    Cleaning the paintwork
    Scratches, corrosive deposits, areas affected by corrosion and damage caused by inadequate care cannot always be completely repaired. In such cases, visit a qualified specialist workshop, e.g. ...

    Load index
    In addition to the load bearing index, the load index may also be imprinted on the sidewall of the tire. This specifies the load bearing capacity more precisely. ...

    Performance to Match Looks
    Despite its size and 4,650-pound curb weight, the CL550 has performance to match its looks. It shares its engine and seven-speed automatic transmission with the S-Class, and as of the 2009 model y ...