NAD L55 Service Manual page 14

E. Picture abnormal
PICTURE ABNORMAL
Check the disc.
Refer to Servo part
If OK
Check PLL IC of MPEG part
YES (If OK)
Check DSP
YES (If OK)
Check MPEG
YES (If OK)
Replace B/D
F. Disc Error
DISC ERROR
Check Disc
YES (If OK)
Refer to Servo part
YES (If OK)
Replace B/D
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