Hello Paul, after parking my BMW X5 E70 for three weeks, it seems the battery is down. I managed to open the driver door manually with the key but cannot access the battery in the boot because the boot doors cannot open with the remote or button switches on the dashboard and boot door. What can I do? Rita
Hello Rita, your BMW X5 E70 battery must have been drained by parasitic computers, which stay active even when the car is switched off, during the prolonged parking without charging. Ordinarily, the trunk lid and lower tail gate (boot doors) have electric locks, which are actuated using the buttons on the front console, trunk lid, lower tail gate and remote key fob. When the battery fails, these buttons cannot electronically open the trunk lid and lower tail gate.
There are two options to charge the battery using emergency charging points under the front hood (bonnet) or accessing the battery located under the trunk (boot) floor.
To find the charging points in the engine bay of your BMW, refer to the car user manual or find someone with technical experience to locate the jumping points at the left side of the engine bay with the positive terminal covered with a red plastic casing.
A portable 12-volt charger will be needed to connect to the positive and negative terminals. Avoid accidentally mixing positive and negative terminals as this will cause severe electrical damage. A quick charge setting can power up the electrical system and enable opening of the trunk lid and tail gate with the electronic switches mentioned above. This will enable access to the battery located under the trunk floor for testing, charging or replacement. In the event that you do not have a portable charger, you could use jump leads and another vehicle to provide 12 volt charge. You need to follow jump starting precautions to avoid electrical damage.
In case a battery charger or donor car with jump leads are not available, the trunk lid and tail gate can be opened manually using a manual release plug on the left side panel in the rear trunk and on the lower tail gate interior upper panel. These points are available in the car user manual.