How do you remove replace the battery in a 2006 BMW M5

The battery is located in the trunk on the passenger side. There should be either a bracket with "2" 13mm bolts or a bracket at the rear of the battery with a long 10mm bolt holding the battery in place (sometimes there will be both types of bolt present). Of course the first thing you want to do is make sure the vehicle is off. It is recommended that you wait at least 3 minutes before disconnecting the battery to ensure the engine computer's relay has fully discharged. Secondly, make sure that you don't have a battery charger or jump box connected to the vehicle at the jump points found under the engine hood. Once that's done and you've removed the brackets you can remove the negative cable first followed by the positive cable (if you are unfamiliar vehicle electrical systems you may want to remove the negative cable before removing any securing brackets). NOTE: the battery is heavy. You may need someone to hold the cables out of the way while you lift the battery out. At this point you can now install the replacement battery following your removal procedure in reverse. Make sure that you connect the positive cable first before connecting the negative cable. Now comes the really hard part. 1) You will need to make sure your replacement battery has the same AH (amp/hour) rating as the original battery. If it does not your vehicle may require programming at you local BMW dealership. Your engine computer controls the output of your alternator based on that rating. 2) You will need to take your vehicle to the dealership to have the new battery "registered" to the vehicle. As a battery ages in your car many systems restrict their operation to prevent complete battery discharge (i.e: a/c blower motor). Simply replacing the battery will not restore these systems to full operation. The car needs to be told that there is a new battery before full function will be restored. Some independent repair shops that are familiar with BMW's may have equipment that can register a battery. You will have to check for availability in your area.