Sharp HT-X1H Service Manual page 49

2. DVD section
• The "No Disc" indication. (In case of focus error)
When removing disc and applying load to spin motor (by stop-
ping with hand, etc.), objective lends moves up and down ?
(Checking item to symptom)
Note: If load is not applied to spin, lens does not move and
becomes NO DISC immediately.
Is FE signal output to pin 40 of U7 when the disc is set ?
Is FE signal inputted into the pin 142 of U9 ?
Check or replace U9.
No
Check the line between theU7 and U9.
• The "No Disc" indicator. (In case focus servo does not function.)
Is there focus control signal at output pin 172 of U9 ?
Is the focus control signal from the pin 172 of U9 input into the
pin 1 of U8 ?
Is the focus control drive voltage output from the pins 13 and 14
of U8 ?
Focus control drive voltage applied to pins 1 and 2 of JB1 (focus
actuator terminal) ?
Check the connection of optical pickup cable.
If it is normal, replace the optical pickup mechanism unit.
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Refer to "The "No Disc" indicator. (In case focus servo does not
function.)".
No
ReplaceU7.
No Is there input signal on the pins 13, 14, 15 and 16 ofU7 ?
Check the connection of optical pickup cable.
If it is normal, replace the optical pickup.
In case of CD.
For DVD, pins 9, 10, 11 and 12 of U7 ?
No Check the U9DAC power source periphery circuit.
If it is normal, replace U9.
No Check the focus control signal (FOD) line between the U8 and U9.
Check M_5 V line.
No Is 5 V voltage applied to the pin 8 of U8 ?
Replace U8.
No Check the line between the U9 and the focus actuator terminal.
7 – 2
HT-X1H
Yes
No
No
Yes