About the service it's very fast and reliable. About the manual the quality is high enough to read even the tiniest details on the wiring diagrams so you can't ask much more than that, let it alone for a manual of a product from 20 years ago. Thank you, very satisfied.
This is a great and complete Service Manual for the Sharp GF8585HB. Giving full and detailed technical insight. Good to find these manuals online.
Text excerpt from page 22 (click to view)
Is the voltage output at IC541 pin "53" 5V or 0V? NO Is the wiring for IC541 (90) ~ (100) correct? NO YES NO YES YES Is 5V present at IC501 pin "20"? YES Check the vicinity of IC541. Is 6V or 3V present at IC501 "10" and "11"? NO Check IC501. Check the feed motor connection wiring. NO Check CD 9V and 5V.
Is 4V present at both sides of the feed motor? YES Check the feed motor.
When the lens is moving: NO Check the circuits in the vicinity of IC501 pins "15" ~ "18". YES YES Check the pickup and its connections.
Does the S-search waveform appear at IC501 pins "6" and "7"?
Is the disk rotated? YES YES Does the RF signal appear at TP1? YES Is the RF waveform at TP1 distorted? YES Proceed to the Tracking section NO Check the circuits in the vicinity of IC521 "16" the pickup Check the spindle motor and its wiring. Check the vicinity of IC501. NO Is 4V present at IC501 pins "8" and "9" ? NO Is 4V present at IC541 pin "55" ? YES NO Check IC521 and IC541.
When the disc is rotated at first: YES Approx. 1.2 V Is the tracking error signal output at IC521 "12"? YES Check IC541. Check the circuit in the vicinity of IC521 pins "2" ~ "12". YES Check the pickup and its connections.