How to Charge a BMW Car Battery

1. Open the trunk and pull up the luggage compartment carpet and floor using the small black looped handle to expose the spare tire and battery compartments.
2. Turn the lock nuts on the battery compartment cover 1/4 turn counter-clockwise. The battery compartment is on the right side of the trunk.
3. Lift the battery cover off the battery to expose the battery terminals.
4. Before you plug the charger in, connect the red (positive) alligator clamp on the battery charger to the positive terminal on the battery. Connect the black (negative) alligator clamp to the negative terminal of the battery. Then plug the charger in. Following this sequence reduces sparking and the chance of and explosion.
5. Turn the battery charger on and set the charger to charge the BMW's battery over a period of 12 hours if the battery was completely dead before the charge.