LG BH5140S Service Manual page 52

2. NO BOOTING WHEN YOU TURN THE UNIT ON, NO MESSAGE OR
"PLEASE WAIT" ON FRONT PANEL
When you turn on your set, it will "PLEASE WAIT" display on front panel, and it will not boot-up
normally.
2-9. MAIN BOARD
2-9-1. Solution
Replace MAIN board.
2-9-2. How to troubleshoot (Countermeasure)
1) Please remove IC501 ~ IC504 and then check the Impedance between each signal (DATA, ADDRESS,
and so on.)
2) If there is some Impedance (a few Ω or infinite Ω) especially power source trace, PCB via might be bro-
ken. You'd better replace MAIN board.
2-9-3. Service hint (Any picture / Remark)
ONE POINT REPAIR GUIDE
< Main board bottom view >
2-37
IC501
IC503
IC504
IC502