JVC KDLH3105
Instrukcja Serwisowa

3.2

Troubleshooting

Feed section
Is the voltage output at IC621 pin "40" 5V or 0V? YES Is 4V present at both sides of the feed motor? YES Check the feed motor. NO Is 6V or 2V present at IC681 "16" and "17"? NO Check IC681. NO Is the wiring for IC621 pin "40"? NO YES Is 3.3V present at IC681 pin "6"? YES Check the vicinity of IC621. YES Check the feed motor connection wiring. Check CD 8V and 5V. NO

Focus section
When the lens is moving: 4V
Does the S-search waveform appear at IC681 pins "13" and "14"?

NO

Check the circuits in the vicinity of IC681 pins "13","14"and"1". YES

YES

Check the pickup and its connections

Spindle section
Is the disk rotated? YES Does the RF signal appear at IC601 pin "19"? YES Is the RF waveform at IC601 pin "19" distorted? YES Proceed to the Tracking section NO Is 4V present at IC681 pins "15" and "16"? YES Check the spindle motor and its wiring NO Check the circuits in the NO vicinity of IC601 pin "19" or the pickup NO Is 4V present at IC621 pins "41" ? YES Check the vicinity of IC681. NO

Check the circuits in the vicinity of IC621 or IC621

Tracking section
When the disc is rotated at first:

YES

Approx. 1.2V Is the tracking error signal output at IC601 "11"?

Check the circuit in the vicinity of IC601 pins "2" to "7".

YES

Check the pickup and its connections

YES Check IC621.
(No.49839)1-25