Troubleshooting (Cd Section) - Sharp MD-X5H Service Manual

When the CD does not function
When the CD section does not operate When the objective lens of the optical pickup is dirty,this section may not operate.Clean
the objective lens,and check the playback operation.When this section does not operate even after the above step is taken,check
the following items.
Remove the cabinet and follow the troubleshooting instructions.
"Track skipping and/or no TOC(Table Of Contents) may be caused by build up of dust other foreign matter on the laser pickup lens.
Before attempting any adjustment make certain that the lens is clean. If not, clean it as mentioned below."
Turn the power off.
Gently clean the lens with a lens cleaning tissue and a small amount of isopropyl alcohol.
Do not touch the lens with the bare hand.
• The CD tray cannot be opened or closed.
Is the following voltage input in the specific IC901 pins 86 and
87 state?
Open state: 86=0V, 87=5V
Close state: 86=5V, 87=0V
Yes
Is H output to the IC2 pin 27 or pin 28 for 7 seconds when
the OPEN/CLOSE button is pressed? IC91 is defective.
Yes
Is 4V output between IC91 pin 3 and pin 7 during operation
above?
Yes
Check the loading motor and loading mechanism.
• The CD function does not operate.
The CD operation button fails to operate.
Yes
Check CD, DSP, power supply, 16.93 MHz clock and reset
terminal.
Yes
Check SCK, SO (DATA) and SI (COMM) waveform.
Yes
Check whether the pickup is in the PICKUP IN switch
position.
Yes
If OK, check the main microcomputer IC901.
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TROUBLESHOOTING (CD SECTION)

No
No
No
– 69 –
Check the OPEN CLOSE switch and the wiring from the IC901
pins 86 and 87 to the OPEN CLOSE switch.
Check the wiring of IC2 pin 27, pin 28, IC91 pin 1 and pin 9.
IC2 is defective.
Check the periphery of IC91.
IC91 is defective.
MD-X5H/CP-X5H
Yes
Yes