Dolphin how to detect whether the battery is good or bad

Dolphins detect whether the battery is good or bad (note: the battery should be charged for an hour and then tested to ensure that the battery is charged)
1. Remove the four screws on each side of the base handrails, and then remove the base handrails

2. Then place the device on its side, remove the screws indicated above, and remove the bottom cover

3. Remove the four fixing screws of the battery, and unplug the three plugs. Pay attention to the label when unplugging the plugs, and insert them back as is after testing 

4. Remove the battery, short-circuit the two pins of the start switch, and use the two pins of the output end of the multimeter. If there is no 24V voltage output, the battery does not charge and needs to be replaced 
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