Moin, I want to bring my MK6 back to life after 1.5 years. Of course the battery is flat. This was installed 4 years ago. Can I recharge it again without any problems? With my Bosch C3 it has unfortunately not worked so far, apparently too little battery voltage. I would like to try it now with an older charger. How do I find out if the batteries are still in order and can be charged? Best regards, BAss