How To Reset A Ryobi Battery. If the red LED light is flashing and the green LED light is off the battery is being tested. Since it is considered to be a power tool battery a Ryobi cell can produce up to 18 volts.
Repeat up to 30 min until it has enough charge to revive itself. The Ryobi 40v charger has a flaw -- when the battery is down to the tool stops running it always flashes defective until you leave it there a while removereplace it a few times until the battery creeps up enough to reset the protection circuit. The battery should normally measure about 18V across the terminals 21V max.
Before planning on rebuilding your Ryobi battery here are a few things you ought to consider.
4 Ways to Fix a Defective Ryobi 40v Battery 1. This should give you a reading and if the voltage reading on the battery is within 0 to 119 volts it means that it is severely discharged or probably dead. Press down on the battery to ensure the contacts engage with each other. Is it OK to leave a lithium ion battery on.
