On many Mercedes-Benz vehicles, the battery location ranges from under the hood to in the trunk, under the rear seat (W210) or under the front passenger seat (w164/166/151).
For vehicles with two batteries, the systems battery will be in the trunk. The starter battery will be under the hood.
It is time to replace the battery in your car now that the old one has been removed.
The old battery must be removed first.
Place the replacement battery in the battery slot.
Does your Mercedes have a slow crank on startup? Does it not start at all?
A good battery will read 12.1-12.9 volts when the vehicle is off.
Double check the amp hours (Ah) and cold cranking amps (CCA) on the battery sticker to be sure that it matches your vehicle specifications.
In some cases, there is a strap wrapped around the battery that can be loosened by finding the buckle, usually located on the side of the battery.
If trunk is where the battery is located, a buckled strap may be used to secure it.
The strap away from the buckle and release the buckle.
The battery connection from the starting battery, which is situated under the hood.
The connection first.
Release the bolt that secures the battery.
The terminal, try twisting it first. Make sure you are not putting too much pressure on it.
Remove the positive battery connection from the circuit.
Would need to wrap it with electric tape.
Position out of the way.
Necessitates the employment of an extension.
While the bracket is out of the way.
To reach the battery on some vehicles, you may need to remove the cabin air filter.
If the cabin air filter box is removed, there are three snap clips on top that hold it to the firewall; use a screwdriver and pop them upward and remove the air filter box.
There are three snap clips on top that hold it to the firewall.
On vehicles with exposed batteries (under the hood), a 10mm wrench or socket is required to remove battery cables and battery top mounts. A 13mm socket and extension are required to remove battery bottom mounts.
Once the new battery is secured into the vehicle, connect the positive battery cable first. Then connect the negative battery cable.
If you connect the negative cable first then the positive, there is a chance the electricity could arc between cable and terminal which could possibly cause a control unit to short out.
On vehicles with two batteries (starter battery and systems battery), usually S-class (221) and SL class (230/231) the starter battery needs to be connected first.
Therefore, if you are replacing the systems battery (in the trunk) you need to disconnect the negative battery cable from the starter battery (under the hood).
Once the systems battery has been replaced you can reconnect the starter battery.
Once the condition of the battery is determined and you have acquired a replacement, double check the amp hours (Ah) and cold cranking amps (CCA) on the battery sticker to be sure that it matches your vehicle specifications.
On the S-Class or AMG S-class (2010 or later) there is a panel at the forward most part of the trunk that can easily come out with the removal of the trunk bottom panel.
The trunk bottom panel has two T20 Torx bolts that sit inside the black plastic hooks bolted to the floor of the trunk.
Once the bolts are removed and the bottom panel comes out, the forward most panel will pivot out from the left side (right side pivoting) and slide out to reveal a space between the forward-most trunk panel and the back of the seat.
In the trunk there is a panel at the forward most part that can easily come out with the removal of the trunk bottom panel.
For starting issues, you will want to replace the battery under the hood.
When you disconnect the battery the windows sometimes forget where they need to start and stop. To reset window normalization, simply roll the window up and hold the button for 5 seconds.
ESP: On all newer vehicles and most older ones, the ESP light will illuminate if the steering angle sensor has lost its positioning.
Resetting the time: On most newer vehicles the car will reset the time itself after being driven around and acquiring a satellite signal.
If trunk is where the battery is located, a buckled strap may be used to secure it. The strap away from the buckle and release the buckle.
When you replace the battery, the car may require initialization or relearning of some systems.
To reach the battery on some vehicles, you may need to remove the cabin air filter. If necessary, a towel or blanket over the fender can prevent body or paint damage when the battery is under the hood.
