LG DP132 Service Manual page 16

When you plug power cord and turn the unit on, LED light won't turn red, the unit won't
read disc nornally .
1-2. Please check main board IC U1 singal and its peripheral circuit.
1) Please check if output voltage 3.3 V from U1 pin4, pin32, pin78, pin83 is normal.
If output voltage 3.3 V is not normal, please check 3.3 V power circuit of main board.
2) Please check if output voltage 1.2 V from U1 pin10, pin77, pin86 is normal.
If output voltage 1.2 V is not normal, please check 1.2 V power circuit of main board.
3) Please check if oscillating frequency 27 MHz of main board Y2 crystal is normal.
If oscillating frequency 27 MHz is not normal, please check if Y2 and its peripheral circuit is in failure.
4) Please check if frequency 135 MHz of U1 pin31 RAM_CLK is normal.
If oscillating frequency 135 MHz is not normal, please check if U1 is in failure.
ONE POINT REPAIR GUIDE
Y2
< Main Board Top View >
U1
3-3