| Problem: I turned my BMC 500+ on to check after about a year. The screen displayed that the battery was at 74%. I charged it for 4 hours with a 5 volt charger.
Whether with the "charged" battery or with it plugged into the charger, when turned on, the device beeps and the screen lights but the screen remains blank no matter which buttons are pushed. The battery tests at 4.18 volts with 49m Ohms of resistance after charging.
Solution: Tech support sent a Youtube showing disconnecting and reconnecting the plug for the screen. I guess one of the multiple mini-connections was not making adequate contact.