Troubleshooting (Cd Section) - Sharp GX-CD555Z Service Manual

When the 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.
Set a disc, turn on the power, set the FUNCTION switch to CD, and check the voltage of CNP881.
schematic diagram being output?
Does the laser go on in test mode l?
Is test mode 1 switched to test mode
Is the output of pin 3 (HF) of TP751
flat in test mode 4?
When the pickup moves to a track
using the UP/DOWN button in test
mode 5, is there audio output?
Yes
When the power is turned off and then
on, is the unit initialized?
Yes
.
Does the disc track up in order
Does the disc play back several ten seconds even
after starting playback?
Yes
When shorting C840 for a moment, does the LCD
function?

TROUBLESHOOTING (CD SECTION)

Check the power circuit of the main unit.
Check the item of " The LCD does not function" .
Check the item of " The laser does not go on" .
Check the item of " Does not focus" .
Check the item of " The spin motor' s CLV servo is defective" .
Check the item of " There is no audio
The pickup in switch is defective (ON).
Check the item of " Track searching is impossible" .
Check the item of " The slide servo does not function" .
No
Check the PWB patterns from pin 1 of CNP881 to CNP951.
No
Check the PWB patterns from pin I of CNP881 to pin 24 (Vcc) of IC750.
Check the LCD PWB of CD.