Try this.

1. Power On while pressing "L1" and "L3".
2. Press "B4".
3. Turn the bender lever to the left, slowly, and go back to
the center, slowly, and then press "B1".
4. Turn the bender lever to the right, slowly, and go back to
the center, slowly, and then press "B2".
5. Push the modulation bar upwards, slowly, and go back to the
center, slowly, and then press "B3".
6. Make sure that the LCD displays "00", "40", and "7F" when
moving the pitch bender and modulation bar.
7. Press "Enter" and Power Off the PCR keyboard.
8. Power On and make sure that the DataOut LED turns on when
moving the pitch bender and modulation bar.