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How to Change the Battery in Your Mercedes-Benz

Post Date: 08th June 2018


So, you’re considering changing the battery of your Mercedes-Benz? Conveniently, Dronsfields have just the thing to get you started – a step by step guide.

First of all, it’d be good to figure out of the issues with your car are directly related to the battery. It’ll apply to more or less every class & model of Mercedes, as the procedure has become quite standard over the years. It should take you no more than twenty minutes.

These are some key signs that any issues you may be experiencing are due to the battery:

– Charging & Visit Workshop Warnings
– Issues with turning the car on after extended breaks from driving, ie in the morning or on your way home from work etc.
– Battery charge draining much quicker than usual

What will I need?

With that in mind, you’ll need a few items to help you with this task:

– A new battery (make sure you’re buying the right battery for your car, especially if you have a Start-Stop model, ensure you don’t buy a Stop-Start battery, and vice versa)
– Old rags you don’t mind getting dirty
Terminal protector
– An 8″ extension
– 10mm and 13mm sockets
– Gloves are highly recommended, in the off-chance hazardous chemicals or electrical shocks occur

Time to replace the battery

1. The first thing you’ll have to do is, find a good spot to park and do your work. Don’t forget to remove the key from the car’s ignition, otherwise you could seriously damage, or outright fry, the electrical components of the vehicle.

2. Once that’s done, you will need to locate the battery. Hopefully you’ll have seen it before, but it’s not an issue if you haven’t. Most models have the battery in the car’s boot, on the right. If it isn’t there, you can google your car’s model and battery location. Under the back seats or in the engine bay is a possibility.

3. Uncover the terminals, and it’s time to make use of your 10mm extension. First, disconnect the negative terminal first. The bolt holding it in place will need loosening first, and if it doesn’t come easily you can try twisting and turning, but trying to brute force it will cause more damage than good. Then, do the same with the positive side, and wrap the tip with electrical tape if you have it on hand, else just ensure that it doesn’t touch anything metal, that again could fry the electrics.

4. Then, you can bust open the frame holding the battery in place, which you’ll now make use of your 13mm extension, and possibly the 8” extension, as it’s usually a tough reach. Once it’s loose, the old battery can be popped free. Be careful not to drop or swing it around the place, as car batteries are a lot heavier than the two AA batteries you shove in the TV remote!

5. Once it’s out, you essentially have to do the same but in reverse. Lower the brand new battery in to the same bay, and give it a good tightening. This is where the battery post needs to be cleaned with a battery terminal cleaner, It can get messy, so rags on hand to clean up the mess and a pair of latex gloves always helps. Once it’s squeaky clean, connect the positive terminal first, then the negative terminal second.

The battery’s replaced! I’m good to go now?

Not just yet, there’s a few more tweaks and tunings you’ll want to perform to get the most out of your new battery. You’ll need to perform a synchronisation of the windows, sunroof if your model has one, and calibrate the steering wheel.

You will have to look into specifics for your car’s time and radio code, as it’s different with every model. Sadly, we can’t go in to hyper specifics here.

Window Sync

With the removal of your battery, the single touch and automatic close actions will be lost, but we can bring them back! Hold the window switches until they close all the way. Once you hear it stop moving, hold it for a few more seconds. Then, lower it all the way and keep the button pressed for the same few seconds. Once you’ve repeated this for every window, you will have regained access to those briefly lost features.

Sun Roof Sync

After the battery change, your sun roof will have safety enabled and only open a fraction of the entire way. Do the same as the windows and close the sun roof and hold the button for 3-4 seconds. Then open it all the way and do the same.

Steering Wheel Calibration & ESP Warning

When all of the above is done and you’ve turned the battery on, you will be greeted by a few lovely error messages, but do not fret. To remove the ESP warning, turn the wheel all the way to the left and hold it. Then, all the way to the right and hold. Go back and forth one more time, then straighten the wheels.

If you restart your car, the ESP warning should have gone and your wheel will be calibrated, and you’re ready to drive!

After all of the above is done and dusted, you’ll be ready to drive on a brand new battery, congratulations! You’ll have saved yourself a few hundred pounds by skipping the garage on this fix. If you have any other issues or would like to ask further, or for any specifics, please don’t hesitate to contact us here.

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