Docking keys - battery warning

socram, Oct 22, 9:18am
Left our vehicle locked for three months with a request for family to start it after six weeks.They couldn't get in and I wasn't sure of the manual key system so we just left it.Only when we returned, did I find out that the emergency key sets off the alarm - until it is docked. Thought that the docking key battery was flat and had to resort to the owner's manual where I found that the key battery is rechargeable - but only when the car has been started!
Incidentally, it fired first time.So, a modern car battery should last three months, but the docking key battery won't last six weeks.