How to Switch Off a Dead Battery
- 1). Turn off whatever device is using the battery if it is possible to do so. A car should have the ignition turned off and the key removed while cell phones should have their screens off. Computers should be unplugged and turned completely off. They should not be left in sleep or hibernation mode.
- 2). Open the device to get to the battery. Most electronic devices have their batteries stored in the back, while cars normally have them stored in the engine block, though some models keep them in the trunk.
- 3). Unhook the battery from the compartment and remove it. Most batteries have two prongs marked positive and negative (usually "+" and "-"). Each will have a terminal connected to it. By pulling these off, there is nothing that can access the battery and it won't be drained further. It can then be properly recharged, tested or replaced. Car batteries may require a wrench to properly remove the connections.
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