Once you see clear signs that your Mercedes is in need of a new battery, it's important to buy a replacement right away. But the cost of replacing Mercedes car batteries can be high. In fact, one popular online car magazine site reported that Mercedes owners were being quoted as much as £1,248 for a replacement Mercedes battery.
That, though, included the cost of installing a new genuine Mercedes car battery, which is why it can be helpful to learn how to fit your own. This can save you labour costs and other additional fees that dealerships and battery shops charge. Here's a guide that can help you do that.
Step 1: Remove your old battery
The first step is to locate your Mercedes battery.
If your battery is under the bonnet, you're going to need a 10mm spanner to remove the top mounts and the cables. Then, use a 13mm spanner to remove the mounts at the bottom. If the air filter box is in the way, then you may need to use a screwdriver to remove the snap clips on top to pull out the box. If there are other cables in the way, just gently move them aside.
If your battery is in the boot, lift the panel in the boot's floor. You'll see the battery either in the middle or to the right-hand side. If there's a strap securing the battery, look for the buckle to release it.
In either case, remove the negative cable first, followed by the positive one.
If your car uses two batteries, though one as a starter battery and one as a systems battery always remember that the starter battery should be the first one to be connected up. Therefore, if you're replacing your systems battery, you need to disconnect the negative cable from the starter battery first. You should reconnect the cable on the starter battery only after you've secured the new systems battery in place.
Once you've disconnected the cables, it's time to remove the old battery.
Step 2: Put the new battery in position
Clean off any dust and grime from the battery tray before putting the Mercedes battery replacement in place. Then, connect the positive cable before connecting the negative one.
Always remember to do it in this sequence. Connecting the negative cable first can cause a short circuit. The same thing could happen if you remove the positive battery first.
Step 3: Reset your system settings
Because your electronic systems are all connected to your battery, replacing an old unit with a new one means you'll have to update some settings.
First, check the dashboard clock to see if it needs to be reset manually. In some cases, you just need to drive the car around and the satellite signal will update the time.
Next, check your windows. Sometimes, replacing the batteries can affect their operation. To revert to the original settings, just roll the window right up and keep your finger on the button until you hear a click. That sound means that the system has locked onto its original settings.
Last, if your vehicle has ESP (Electronic Stability Control), a yellow triangle-shaped light may appear on the dashboard to indicate that the steering angle sensor has lost its positioning. Rectify this by starting the engine and turning the steering wheel from lock to lock until the light goes off.
If you have problems with identifying the right replacement battery for your vehicle, you can trust our battery experts here at Orius Batteries to guide you through the process. Just call us on 01772 348317 and let us know what make and model you have, and we'll be happy to advise on your options.
FREQUENTLY ASKED QUESTIONS
How long do Mercedes batteries last?
With proper maintenance, a genuine Mercedes car battery can last up to four years. However, if you’ve bought a cheaper replacement, you may only get around two years out of it before it starts to show signs of failing. On the other hand, high-quality batteries can last as long as six or more years.
What type of battery does Mercedes-Benz use?
Any new Mercedes Benz battery must match the old battery’s group size. Absorbent glass mat (AGM) batteries that can cope with a high accessory load are the best for this kind of vehicle. Most of this manufacturer’s models are fitted with an AGM H8 battery. A replacement battery should be a Group 49 AGM one.
Does Mercedes have two batteries?
Some models do have two batteries. In such cases, you’ll find the main starting battery in the boot and the other under the bonnet, near the windscreen on the car’s passenger side. Two batteries are needed for cars with high electrical demands. The Mercedes charging system has been refined to balance the alternator’s output between the two batteries.
Can you charge a Mercedes battery?
Yes, but it’s inadvisable to charge a Mercedes automobile battery while it’s still installed in the vehicle unless you’re using an approved Mercedes-Benz battery charger unit. Otherwise, dangerous fumes can be emitted, which can cause explosions, resulting in corrosion, paint damage, and even personal injury.
What does the auxiliary battery do in Mercedes?
Mainly, it provides power for the start/stop function and some or most of the car’s accessories like PDC sensors, multimedia, and different radars. The standard battery starts the car and runs some of the more basic accessories, like the radio, clock, and so on.
Charging A Mercedes-Benz Car Battery
How to safely charge a Mercedes battery:
- Only use chargers approved by Mercedes-Benz.
- Charge the Mercedes vehicle battery if its voltage is lower than 12.2V, but only if the warning lamps are lit up in the instrument cluster.
- Only use battery chargers with a maximum voltage of 14.8 V.
- While charging, deactivate the start/stop function to prevent injuries.
- When jump-starting, connect the charger to the positive clamp and earth point in the same order as the donor battery.
- Make sure there is enough ventilation.
How To Replace The Battery On A Mercedes-Benz
Step 1: Park the vehicle in a safe spot.
Step 2: Find the Mercedes car battery location on the right-hand side of the boot or under the bonnet.
Step 3: Remove the negative terminal, then the positive terminal; then the bracket that holds the dead battery in place. Lift out the battery.
Step 4: Place the new battery in the tray then reattach the brackets, then the positive and negative terminals.
Step 5: Synchronise the windows and sunroof, then adjust the steering wheel.
Step 6: Reset the clock.
Step 7: Enter the radio code.
Guide To Replacing A Mercedes Car Battery
Step 1: Locate the battery - usually found in the bonnet or the boot.
Step 2: Using a voltmeter, check the voltage by contacting the probes to the positive and negative terminals.
Step 4: Using a 10mm spanner, remove battery cables to lift the old battery up.
Step 5: Secure the new battery in place, then connect the positive cable first followed by the negative one.
Step 6: Reset the time, normalise the windows, and clear any ESP light.
If you're looking for the best value for money when buying a new Mercedes automotive battery, including options from big-name sellers like Bosch, Varta, and more, check out our wide range of products on our website shop at Orius Batteries. We even offer free delivery on orders in the UK.