LG DR1F9H Service Manual page 75

Track Servo is unstable
Is TE signal
output normal in Focusing
ON and Tracking OFF?
(LIC121 pin 24*)
YES
Is there TDRV
signal output in Tracking ON?
(LIC201 pin66)
YES
Check the Drive IC(LIC301) and
P/U referring to "Focus Actuator
operating is abnormal".
NO Is PICK UP
(E, F, G, H) output normal?
(LPM101 pin 8, 5, 9, 4)
YES
Replace LIC121.
NO
Replace LIC201.
4-8
NO
Check the PICK UP FFC.
Replace the PICK UP.
* LIC121 pin24 is MOUT1(FEP Monitor1).
After disc recognition action, Monitor port
is off. So, please check TE signal during
disc recognition.