2003 Mercedes C-Class Owner's Manual - Page 286

Practical hints Unlocking/locking in an emergency Locking the vehicle If you are unable to lock the vehicle with the SmartKey, lock it with the mechanical key as follows: Close the passenger doors and the trunk. Press the central locking switch in the cockpit ( page 92). Check to see whether the locking knobs on the passenger doors are still visible. If necessary push them down manually. Lock the driver's door with the mechanical key ( page 285). Check if the trunk is locked. If necessary lock the trunk with the mechanical key ( page 90). Changing batteries If the batteries in the SmartKey are discharged, the vehicle can no longer be locked or unlocked. It is recommended to have the batteries replaced at an authorized Mercedes-Benz Center. Warning! i When changing batteries, always replace both batteries. The required replacement batteries are available at any Mercedes-Benz Center. G Keep the batteries out of reach of children. If a battery is swallowed, seek medical help immediately. Batteries contain materials that can harm the environment if disposed of improperly. Recycling of batteries is the preferred method of disposal. Many states require sellers of batteries to accept old batteries for recycling. 286