The Spindle Motor Fails To Run.does The Head Move; Recording/Playback Operation - Sharp MD-MT831H(GL) Service Manual

• The spindle motor fails to run.Does the head move

Does the waveform appear on the IC201 pins 24 and 25 after
TEST mode AUTO2 completion and in this state?
Does waveform appear on the IC601 pin 64?
Does waveform appear on IC601 pins 25, 27 and 29?
Replace the spindle motor.

• Recording/playback operation

Insert a low reflection disc, and ascertain audio output by normal playback, and then set TEST REC mode.
Does the head move down, failing to start record even
when the continuous record mode is set after address?
Does the RF waveform appear at TP201 (when monitoring
the RF waveform, set to MSL:80H using the control setting
item of EEPROM) when recording/playback is performed?
Is the level during recording different from that during
playback at the pin 86 of IC401?
Is RF pattern output from IC201 pin 50?
Check whether there is any damage in IC101, periphery of
laser diode.
Check for defects of IC351 in head drive flexible PWB,head,
flexible PWB.
Is audio monitor output given in normal mode LINE IN
record?
Is waveform obtained on IC501 pins 3 and 6?
Is audio waveform observed on the pins 18 and 19 of
IC703?
Check whether input waveform is observed on the pins 8
and 17 of IC703.
Yes
Yes
Yes
No
No
Yes
Yes
No
No
Yes
Check the IC201 periphery.
No
Replace. IC601
No
L608, IC201, IC601, CN601 and flex, etc. soldering check
No
Check voltage of pins 57 and 58 of IC201, pins 37, 38, 45, and
Yes
47 of IC601, pins 1 and 2 of CN601. Check whether disc is
record-inhibited.
Yes
Check periphery of IC401 and IC101.
No
Check for soldering failure of IC201 .
No
Check waveforms of pins 9 to 12 of IC501, pins 70 to 73 of
Yes
IC201.
Check whether the pin 7 of IC501 and the pin 81 of IC201 are in
H state.
Yes
Does voltage on the IC701 pins 13 to 15 change in case of
No
record VOLUME UP/DOWN?
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MD-MT831H/W