Panasonic DVD RECORDER DMR-EX75EB

Stopped working U61 came on. This unit has found an error during recording or playback without an inserted disc.The unit proceeds with recovery procedure. The procedure restores thenormal operating mode.The unit is not defect.Please wait untill message goes off. Screen says SELF CHECK DID NOT COMPLETE1 PRESS ENTER THE UNIT OPENS THE DISC TRAYAND TURNS TO STANDBY. 2PRESS POWER TO RESTART. I presume power is the standby _off button. It does not say power in any part of diagram. I followed instructions and allways ended up showing goodbye then tray comes out again. Press tray in again.It goes in, again it says U61.