Enter the following code at the Password screen:

Level 2: HTDC
Level 3: CLLD
Level 4: LBKG
Level 5: XDDJ
Level 6: FXLC
Level 7: KRFK
Level 8: KLFB
Level 9: DDRX
Level 10: HRTB
Level 11: BRTD
Level 12: TFBB
Level 13: TXBB
Level 14: CKJL
Level 15: LFCK