Feed section
Is the voltage output at NO IC621 pin "40" 3.3V or 0V? YES Is 4V present at both sides of the feed motor? YES Check the feed motor. NO Is 6V or 2V present at IC681 "4" and "5"? NO Check IC681. Is the wiring for IC621 (56)~(64) correct? NO YES Is 3.3V present at IC681 pin "20"? YES Check the vicinity of IC621. YES Check the feed motor connection wiring. NO Check CD 8V and 5V.
Focus section
When the lens is moving: 4V
Does the S-search waveform appear at IC681 pins "10" and "11"?
NO
Check the circuits in the vicinity of IC681 pins "10","11"and"14". YES
YES
Check the pickup and its connections
Spindle section
Is the disk rotated? YES Does the RF signal appear at TP1? YES NO Is 4V present at IC681 pins "6" and "7"? YES Check the spindle motor and its wiring NO NO Is 3.3V present at IC621 pins "41" ? YES Check the vicinity of IC681. Check IC621 and IC601. NO
Is the RF waveform at TP1 Check the circuits in the distorted? NO vicinity of IC601 "19"~ "24" or the pickup YES Proceed to the Tracking section
Tracking section
When the disc is rotated at first:
YES
Approx. 1.2V Is the tracking error signal output at IC601 "11"?
Check the circuit in the vicinity of IC601 pins "2"~"12".