Mercedes Car Battery Replacement Service

The process of replacing the car battery of Mercedes Benz is fairly easy. You require a replacement car battery and a few basic tools. Beyond that, knowledge of the car battery’s location in the car, battery model as well as the process of disconnecting it is required. It is also imperative to know when to replace the battery.

Identifying that the car battery needs to be replaced- The most common sign to identify that the battery requires replacement is when you notice that it gets difficult to start the vehicle each day. If it takes several seconds just to get the power running, the car battery reaching it’s end of life. If the engine sputters for several seconds after turning the key or fails to start, the battery is dead. There is also a battery charging malfunction indicator on the car’s dashboard.

Precautions to take while changing the Mercedes car battery

While changing the car battery, always be careful to avoid a short circuit. Avoid contact between positive and negative terminals, and positive terminal and the frame of the vehicle.

Tools required

Before attempting to replace the car battery, you need to have the following tools at your disposal. You will need a 10mm socket wrench to disconnect the battery from positive and negative terminals, 13mm socket wrench to take out the bracket that holds the battery in place, 8” extension to loosen the battery from its terminals, and the battery post cleaner to clean the empty battery post.

Replacing the Car Battery

Secure and park the car firmly- Make sure that you park the car on a layer of concrete with the emergency brakes fully extended. This will help the car stay in place while replacing the battery preventing any damage to neighboring parts in the process.

Finding the car battery

In most Mercedes Benz models, the battery is located on the right on the inside of the trunk. In rarer models, its located beneath the back seat. If the vehicle contains two batteries, check the trunk for the system battery and beneath the hood for the starter battery.

Removing the car battery

To remove the battery, first, unplug the negative battery terminal. Loosen the 10mm bolts that secure the battery in its place. Next, you need to unplug the positive terminal. Insulate this section to ensure that the positive terminal doesn’t make contact with any part of the car, including the car frame. Take out the bracket that is holding the battery in its place. The bracket is secured with a 13mm bolt and requires an extension to loosen. Now, you can remove the dead battery from the car. Be cautious as the battery is going to be quite heavy.

Exclusive Circumstances

On some models, you will have to remove the cabin air filter to access the battery. If the battery is located in the trunk, it will be wrapped with a strap. Remove the strap and the battery can be removed. On the S- Class and the AMG S-Class series, the bottom panels are secured with T20 Torx Bolts. On (221) S-Class and (230/231) SL class, locate the starter battery under the hood and disconnect its negative cable before removing the system battery. After installing the new system battery, reconnect the starter battery.

Installing the car battery

The process of installing the battery is the reverse process of removing the battery. In order to install the new battery, take and place it in the battery bracket. Next, put the bracket into the battery place and tighten the bolts. Reconnect both negative and positive terminals respectively.


The final step before you can start using your car is synchronizing the new battery with the various features of the car.

  1. Windows- Press and hold the window switch until the window is fully closed and continue pressing the button for three more seconds. Then, press the button to fully lower the window and then hold the button for three more seconds. Do the same for all the windows to fully calibrate the windows of your car
  2. Sunroof- Press and hold the button to fully open the sunroof and continue holding the button for three seconds. Next, press the button to fully close the sunroof and continue holding the button for three seconds to fully calibrate the sunroof.
  3. Steering Wheel- The moment you start the car with the new battery, the dashboard starts to show an ESP message. To reset ESP, turn the steering wheel to the extreme left and hold it there for two seconds and then turn the steering wheel to the extreme right and hold it there for two seconds. Now, shut down the car and restart it to calibrate the steering wheel as well as turn off the ESP message.
  4. Set the Time and Date- After reinstalling a battery, you are required to set the time and date from its factory settings.
  5. Radio Code- On some car models, you are required to synchronize the radio with the battery. You can refer to the user manual to check the process of synchronizing the radio from factory default settings.

The process of replacing the battery in Mercedes Benz cars is fairly simple if you have the tools required to carefully remove the old battery and install the new one. Some car models have a slightly different method in replacing the battery due to have dual batteries and the batteries being located in different areas of the car. Calibrating the features of the car after replacing the battery can be a little difficult if you are new to Mercedes Benz cars or have never done before. If the battery gets faulty during an emergency and you find difficulty in replacing the battery or do not have the required tools, we strongly recommend you to contact FastFix at 81145500 for immediate professional service and assistance.

WhatsApp Click to WhatsApp