LG HB905PA – SB95PA-F/S/C/W - COMPONENT REPAIR HELP

ABNORMAL MD OPERATION

Abnormal disc reading or abnormal tray open/close. => Replace new MD and test if it is operated normally.

Component

• Traverse assembly
• MD junction board
• FFC cable from main board to MD

Troubleshooting  (Countermeasure)

1. Check the connection between main board and FFC cable, confirm the connection point.
2. Check the connection of MD junction board cable.
3. If all the cable connections are normal, replace the traverse assembly.

After changing MD (Traverse assembly), you must perform "SA Reset". [Refer previous post here]

HB905 series MD Top & Bottom views.

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.

Component

• MD (Traverse Assembly)
• SIC707 – Adjustable LDO

Troubleshoot

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 BD LD Control input/output.  If input signal (LTHR_LPF) is ok But no output (LDI_BD), Check the TR SQ714, SQ716.

ALL DVD DISC READING ERROR

• All the DVD disc is not operated, but BD and CD are operated normally.
• If the LD current control is abnormal, DVD doesn't work.

Component

• MD (Traverse Assembly)
• SQ712, SQ717

Troubleshoot (Countermeasure)

1. Check MD (Traverse, pick-up) first of all.
2. Check the DVD LD Control input / output.

If input signal ( LDELO_LPF) is ok, but no output (LDI_DVD), check the TR SQ712, SQ717.

ALL CD DISC READING ERROR

• All the CD disc is not operated, but BD and DVD are operated normally.
• If the LD current control is abnormal, CD doesn't work.

Component

• MD (Traverse Assembly)
• SQ713, SQ715

Troubleshoot (Countermeasure)

1. Check MD (Traverse, pick-up) first of all.
2. Check the CD LD Control input / output.

If input signal ( LDEL1_LPF) is OK, but no output (LDI_CD), check the TR SQ712, SQ717.

ABNORMAL SERVO OPERATION

• The actuator, spindle and sled operation of pick-up are abnormal.
• After changing MD, the motors are abnormal operations.
• After changing Motor Drive IC, the motors are abnormal operations

Component

• MD (Traverse Assembly)
• SIC706 – LM358

Troubleshoot (Countermeasure)

Check if the input/output voltage of SIC706 (Pin5 and Pin7) is 1.67 V

CLICK ON PICTURES TO MAGNIFY