Sound In Portable Mode - LG NP5550B Service Manual

2. NO SOUND IN PORTABLE MODE
No sound problem occurs in portable mode.
2-1. Solution
Check and replace IC500 on main board.
2-2. How to troubleshoot (Countermeasure)
1) Check solder of JK300.
2) Check if signal enters pin2 and pin7 of IC500.
3) Check if signal comes out from pin63 ~ 66 of IC500.
  If it doesn't work, replace IC500.
4) Check if signal comes out from CN700 L+, L-, R-, R+.
  If it doesn't work, replace IC700.
2-3. Service hint (Any picture/ Remark)
IC500 IC500
ONE POINT REPAIR GUIDE
< Main board top view >
CN700 CN700
< Main board bottom view >
IC700 IC700
3-3
JK300 JK300
< I/O jack board top view >