2003 Mercedes CLK-Class Owner's Manual - Page 312

Practical hints Unlocking/locking in an emergency Changing batteries If the batteries in the SmartKey or the SmartKey with KEYLESS-GO* 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. SmartKey / SmartKey with KEYLESS-GO* Remove mechanical key 1 ( page 310). Insert the mechanical key in side opening and push gray slide. The battery compartment is unlatched. Pull the battery compartment out of the key housing in direction of arrow. Remove the batteries. 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. 1 Mechanical key 2 Battery compartment Replacement batteries: Lithium, type CR 2025 or equivalent. 3 Battery 4 Contact spring 312