All Bd Disc" Reading Error - LG LHB535 Service Manual

COMPONENT REPAIR GUIDE
2. "ALL BD DISC" READING ERROR
=All the Blu=ray disc is not operated, but DVD and CD are operated normally.
= If the LDO for APC of BD laser diode is abnormal, BD doesn't work.
= If the LD current control is abnormal, BD doesn't work.
2=1. Component
1) MD (Traverse Assembly)
2) SIC707-Adjustable LDO
2=2. How to troubleshoot (Countermeasure)
1) Check MD (Traverse, pick-up) first of all.
2) Check input/output voltage of LDO SIC707 (12 V, 8 V).
3) If output voltage is abnormal, check the periphery of SIC707 and replace it.
4) Check the BDLD Control input/output.
If input signal (LTHR_LPF) is ok But no output (LDI_BD), Check the TR SQ714, SQ716.
2=3. Service hint (Any picture / Remark)
NPUT(FROM MAIN CHIP)
"" ....... _SR755 SC759F"_- - -
OGNO
Q7£4
_4MBT3904LTiG
-SR765
470
SR790 S _
_/_ LDZBD _ OUTPUT(TO PICK-UP)
LH_li7 ADd
VCC /_V LOADER
12V
SC741
O_ND
_R762
_. 71<(!:
DGND
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