In this guide, you will find the procedure on how to replace the battery on a Mercedes-Benz. Replacing the car battery on a Mercedes-Benz is easy and can be completed by any DIYer. These step-by-step instructions on how to replace Mercedes battery should help owners of E, C, S, ML, CL, CLK, GL, GLK, CLA models change the battery themselves.
Aftermarket Mercedes-Benz Batteries
- Exide Edge FP-AGML4/94R Flat Plate AGM Sealed Automotive Battery
- ACDelco 94RAGM Professional AGM Automotive BCI Group 94R Battery
In this article:
- How to replace Mercedes Battery – DIY Instructions
- How to Synchronize a Mercedes-Benz after battery replacement
- How to avoid losing the memory
- Mercedes-Benz Dealer Battery Cost
- Choosing the Best Battery for Mercedes
- Mercedes Replacementacemenet Warranty
Signs that the battery needs to be replaced include:
- Hard time starting the Mercedes in the morning
- Warnings related to Charging System Malfunctioning
- Electrical Consumers switched off
- When you get this warning the issue may be the secondary (auxiliary) battery, not the main Mercedes battery.
- Visit Workshop Warning
During the process of removing and installing a new battery on your Mercedes-Benz, you need to be extremely cautious and avoid a short between the positive terminal and the body or the negative terminal.
- 10mm socket
- 13mm socket
- 8″ extension
- Battery post Cleaner
- Battery Terminal Protector
- Replacement Mercedes Battery
(OEM or Aftermarket)
Mercedes Battery Removal Procedure
- Park your Mercedes-Benz. Engage the parking brakes. Remove the key from the ignition. This is important to avoid damage to electrical components.
- Locate the battery. Most Mercedes-Benz cars have the battery located in the trunk on the right side. A few models such as W203, R170 etc have the battery in the engine bay, passenger side. While some models have the battery under the rear seat.
- Disconnect the negative battery terminal first. You will need to loosen the 10mm bolt and pull the terminal away from the post. If the terminal doesn’t come out very easily, try twisting the terminal then pull it. Don’t use extreme force. If the battery cable clamp is stuck, use a battery terminal puller.
- Disconnect the positive battery terminal. Insulate the positive battery terminal with electrical tape. You want to make sure that it doesn’t accidentally touch the frame or any metal part of the car.
- Remove the bracket that holds down the battery. This is a 13mm bolt. You will need to use an extension to get to the bracket in most cases.
- Remove the old battery from your Mercedes-Benz. Use caution when removing the old battery as car batteries tend to be heavy.
Mercedes Battery Installation Procedure
Battery installation procedure is the opposite of removal.
- Lower the new battery in the battery tray.
- Install the battery bracket.
- Clean battery post using a battery terminal cleaner.
- Connect the positive battery terminal first.
- Connect the negative battery terminal last.
After you install the new battery in your Mercedes-Benz, there a few synchronization procedures that you need to perform. Follow the instructions below to sync your Mercedes and complete the battery installation procedure.
The one touch or auto close window functions will be lost. Press and hold the window switch until the window closes completely.
- Press and hold the window switch until the window closes completely.
- Once the window reaches the top, continue to hold the button pressed for an additional three seconds.
- Lower the window and continue to hold the button pressed for an additional three seconds after the window is fully lowered.
- Repeat this procedure for the other windows.
Synchronize sun roof
When you try to open the sunroof it will only move a couple of inches then stop. To fix this follow this procedure:
- Press the switch to close the sunroof all the way.
- Once the sunroof is closed continue to hold the switch for another three seconds
- Move the sunroof all the way to the back. Once the sunroof reaches the back, continue to hold the sunroof for an another three seconds.
Calibrate steering wheel
Once you complete the battery replacement on your Mercedes-Benz, start up your Mercedes-Benz. You will be greeted with a couple of warning messages such as ESP warning light but don’t panic. To reset the ESP warning follow this procedure:
- Start up your Mercedes-Benz
- Turn the steering wheel all the way to the left and hold it there for two seconds
- Turn the steering wheel all the way to the right and hold it there for two seconds
- Repeat procedure one more time. Straighten the wheels
- Turn off the car and restart it. The ESP warning light should be off
Follow the instructions to set the time. You will have to use the buttons on the steering wheel or the command buttons to set the clock on your Mercedes-Benz. Each model is different so we can’t provide instructions on how to set the time here.
Several Mercedes Benz models require that you enter a radio code after the battery replacement. You may be required to enter a radio code. This is often printed on the owners manual. If you can’t find the radio code, call your Mercedes-Benz dealer. They can look up the radio code if you provide the VIN.
You can avoid having to perform synchronization procedures by connecting a backup power source to your Mercedes-Benz before you disconnect the old battery. The backup battery or a jump starter will need to be connected at the jump starting terminals which are located under the hood, regardless of whether the main battery is under the rear seat, trunk or engine bay.
- Locate the positive battery terminal used for jump starting. It has a red cover. You will need to slide the cover to see the positive post.Next to the positive post you also have a negative post as well.
- Connect your jumper starter or 12 volt back up battery source. Lithium jump starters such as NOCO Jump Starter work great great for this purpose.
Mercedes battery replacement cost (dealerships in the US) varies between $280 and $400 in 2017. That includes the cost of a new car battery and the cost to install the battery. Note that this is the price for the main battery, not the smaller secondary (auxiliary) battery.
For example, let us look at the price to replace the main Mercedes battery in two vehicles, an S-Class and C-Class. Below are the prices how much it would cost to buy the battery at the dealer and how much it will cost to have the dealer replace the battery
- 2012 Mercedes-Benz S350 Blue Tech
- OEM Mercedes Battery Price: $247
- Installation Price: $140
- 2011 Mercedes-Benz C300 4-Matic
- OEM Mercedes Battery Price: $165
- Installation Price: $140
Cost to replace Mercedes battery yourself
By replacing your Mercedes-Benz main battery yourself, you have the potential to save between $100-$200. Replacing the battery is easy and takes less than $20 min. You can buy the battery from the dealer and install it yourself saving the installation cost or buy an aftermarket battery that meets the OEM battery specs.
If you spend some time searching for an aftermarket battery that meets Mercedes specs you will find there are a few good alternatives. When choosing a battery for your Mercedes you need to make sure it is the same group size. Generally speaking, most Mercedes-Benz cars use AGM H8 battery. If you are shopping for a cheap Mercedes battery search for Group 49 AGM Battery. Absorbed Glass Mat (AGM) batteries are recommended due to high accessory load on Mercedes vehicles. You also need to find a battery with similar Cranking Amp (CA) and Reserve Capacity (RC).
These values are printed on top of the old battery or can be verified by calling your Mercedes-Benz dealer.
Typical Mercedes battery:
- Group Size: H8 / Group Size 49 / 94
- Battery Type: AGM
- Cold Cranking Amps: 850
Mercedes Battery Size
Most Mercedes-Benz cars use BCI Group 49 Battery. We wrote an in-depth article about choosing the best battery for Mercedes-Benz.
Two of our favorite batteries that are worth considering are:
As of July 2017, Mercedes-Benz OEM batteries come with a two year (24-month) warranty. Once the Mercedes battery warranty is over, it is the customer’s responsibility. There is no prorated coverage.
While a two-year battery warranty is better than some aftermarket batteries that come with a one year warranty, it certainly isn’t the best battery warranty out there. Several aftermarket AGM type batteries that fit Mercedes-Benz cars perfectly, come with at least three-year warranty. Increasing the warranty period would be something Mercedes-Benz should consider to improve customer satisfaction.
Replacing the battery on a Mercedes-Benz car is easy and straight forward. The whole process of installing a Mercedes battery takes about 20 minutes. When you compare Mercedes-Benz battery replacement procedure with the procedure to replace the battery on a BMW, Mercedes is much simpler and easier. On BMW cars when you replace the battery, you also need to program the new battery and clear the charging history of the old battery from the power module which can only be done with a special scan tool. You don’t have to do any of that on a Mercedes-Benz except to synchronize the windows and sunroof which requires no tools and only takes a couple of minutes. We will show you how to do that in this guide. Aren’t you glad that you didn’t buy a BMW?