Our Crown RC5530-30 periodically gives us the error code of 201. It happened to us last week, and the operator noticed the battery was low so after a full charge it worked as it should. Now the battery is mostly charged but began giving us the error again and stops the lift. It will go forward and reverse in slow speed but if you speed up or try to lift the forks, it will lock out and give this code. Any help would be appreciated. We just purchased this machine used about 6 months ago and the battery was refurbished in 2019 roughly.