2009 Mercedes CLS-Class Owner's Manual - Page 325

Practical hints Battery G Warning! Failure to follow these instructions can result in severe injury or death. Never lean over batteries while connecting, you might get injured. Battery fluid contains sulfuric acid. Do not allow this fluid to come in contact with eyes, skin or clothing. In case it does, immediately flush affected area with water and seek medical help if necessary. A battery will also produce hydrogen gas, which is flammable and explosive. Keep flames or sparks away from battery, avoid improper connection of jumper cables, smoking etc. G Warning! Do not place metal objects on the battery as this could result in a short circuit. Use leak-proof batteries only to avoid the risk of acid burns in the event of an accident. ! The battery is a Valve-Regulated Lead Acid (VRLA) battery, also referred to as "fleece" battery. Such batteries do not require topping-up of the electrolyte level. VRLA batteries therefore do not have cell caps and the battery cover is non-removable. Do not attempt to open the battery as otherwise the battery will be damaged. Even though VRLA batteries do not require topping-up of the electrolyte level and cannot be opened to check the electrolyte level, the battery condition must be checked periodically by performing a battery conductance test. Refer to Maintenance Booklet for battery condition testing intervals. The factory-equipped VRLA battery is leakproofed. Only use a battery as replacement that has the same security features and is of identical size, voltage, and capacity as the factory-equipped battery. The battery, the battery ventilation hose and the lateral plug must always be securely installed when the vehicle is in operation. ! Never loosen or detach battery terminal clamps while the engine is running or the SmartKey is in the starter switch or KEYLESS-GO button is in position 1. Otherwise the alternator and other electronic components could be severely damaged. Have the battery checked regularly at an authorized Mercedes-Benz Center. Refer to Maintenance Booklet for maintenance intervals or contact an authorized Mercedes-Benz Center for further information. i Only replace a discharged battery with a battery recommended by Mercedes-Benz. i After battery power was interrupted, do the following: RSynchronize the power windows (Y page 104). RSynchronize the tilt/sliding sunroof (Y page 173). Z ! As with any other battery, have the battery disconnect at a qualified workshop or an authorized Mercedes-Benz Center if you do not intend to operate your vehicle for an extended period of time to prevent battery discharge. You may also connect an accessory battery charge unit expressly approved by Mercedes-Benz for your vehicle model to maintain the battery charge. Contact an authorized Mercedes- Benz Center for further information. 323