Contents: Removal ↡ Installation ↡
Do not loosen or remove battery cables while the engine is running. Otherwise, electronic components may be damaged (for example, a generator).
Attention! Disconnecting the battery will result in the loss of data in the electronic memory units of the vehicle, such as data in the engine fault memory, the radio code that protects it from theft, or programs entered into the radio memory. Therefore, it is necessary to find out and write down the code first. Otherwise, the radio can only be restored to operation with the help of a Mercedes-Benz service station or the manufacturer.
Note: Since mid-2002, MERCEDES-BENZ has not supplied radio receivers with codes, since the vehicle electronics recognize the radio receiver after the battery is connected.
To avoid losing saved data, you can connect an auxiliary power source. Before disconnecting the battery, connect it to the cigarette lighter in accordance with the manufacturer's instructions.
Removal
1. Switch off all electrical consumers. Switch off the ignition. This will prevent damage to the electronic control devices.
2. Open the hood. The battery is located on the front passenger side under the cabin air filter box.
Models with TeleAid system: To avoid discharging the emergency power supply battery when the vehicle battery is disconnected, the telephone should be set to maintenance mode (separate "Telephone Operating Manual").
3. Remove the cabin air filter box, refer to Section Replacing the cabin air filter element/carbon air filter.
4. Disconnect the battery cables, negative cable first, then positive cable.
Note: Before disconnecting the positive cable, the cover over the positive terminal must be removed.
After disconnecting the battery terminals, the key in the ignition switch no longer turns, and the AT lever remains locked in the "P" position.
5. Unscrew the 2 nuts and remove the mounting plate at the base of the battery.
6. Remove the battery from the engine compartment.
Installation
1. Before installation, clean the battery terminals until they shine. A brass wire brush is suitable for this purpose.
2. Replace the battery, the mounting plate at the base of the battery and secure it.
3. Before connecting the battery, check that the ignition and all consumers are turned off.
4. First connect the positive cable to the positive (+) terminal, then the negative cable to the negative (-) terminal of the battery.
Note: Incorrect battery connection may cause serious damage to the generator and other electrical devices.
5. Apply a thin layer of petroleum jelly to the cable and battery terminals to protect against corrosion. Do not lubricate before connecting.
6. Place the cap on the positive (+) terminal.
7. Reinstall the cabin air filter box, refer to Section Replacing the cabin air filter element/carbon air filter.
8. After connecting the battery, the following work must be carried out:
- Setting the clock (Section Multifunctional steering wheel, universal display).
- Re-aligning the side windows (Section Power windows, sunroof).
- Re-aligning the panoramic sliding roof panel/sunblind (Section Power windows, sunroof).
- Re-adjust the ESP system. To do this, turn the steering wheel from lock to lock with the engine running.
- Headrest adjustment.