Replace the Battery in a BMW E91

This tutorial shows you how to replace the battery in a BMW E91. Open the trunk, lift and remove the floor cover. Use a flathead screwdriver to unscrew the two plastic retainers located on the right side of the compartment and detach the carpeted side panel.

Now, to remove the battery compartment cover, rotate the two plastic fasteners; you now have access to the battery. Using a 10 mm socket wrench, unscrew the upper bracket; then detach the strap supporting the battery cables.

Using the socket insert, remove the negative terminal bolt and disconnect it (you can cover the terminal with a latex glove to prevent accidental contact). Disconnect the incoming cables from the positive terminal by acting on the retaining clips.

With the flathead screwdriver, remove the clips located on the sides of the positive terminal; use the insert to unscrew the positive terminal fastening bolt and you can extract it. Detach the other cable ties to move the wires aside and easily remove the battery.

The video also mentions the presence of a battery hold-down bracket, which can be easily removed by unscrewing the visible screw on the side of the battery.

Now, insert the new battery into place and to install it, reverse the disassembly steps.