Never format a SD card from a machine. It contains software and machine information and you will lose them.
Try to find a new one or if you know a working machine you can try to clone the SD.
Please your help, I have a workcentre 3345 printer that suddenly went into a power loop.
When you open the power switch the printer turns on all the lights and the screen shows the ENERGY STAR logo, then a couple of seconds everything turns off and a moment later the lights and the ENERGY STAR logo come back on.
It stayed in that cycle indefinitely, I have tried leaving it disconnected for a while, opening and closing the power switch but nothing has changed.
I look forward to your comments.