LG CM8440 Series User Manual

3-12
ONE POINT REPAIR GUIDE
NO OPERATION OF MD (DRIVING THE SERVO MOTORS)
When no sound output in the CD function, you can not listen to music reading data
from a CD disc if the servo motors in MD don’t work. This step is for checking the
SLED MOTOR among them.
5-2. SLED MOTOR
5-2-1. Solution
Please check and replace IC407, IC408 on MAIN board.
5-2-2. How to troubleshoot (Countermeasure)
1) Check the SLDO signal from Pin23 of IC407.
 If no signal, check 3.3 V(RF) and X400.
2) Check the SLED+ & SLED- from IC408 to CN405 for driving SPINDLE motor. It is about 2.9 Vp-p.
 If no signal, check +1.8 V and +5 V for IC408.
3) Check if the FFC cable is solidly connected between CN405 and MD.
4) Check the MD.
 If the sled motor is sort-circuit or has any trouble, it can not move the pick-up module.
Please check the function after changing another MD.
5-2-3. Service hint (Any picture / Remark)
zsR
zsT
zsR
^GGju[W\
zsT
`GGju[W\
pj[W_G
< Waveform of SLED- & SLED+
for driving SLED motor >
< Signal check point >

LG CM8440 Series Specifications

General

Brand	LG
Model	CM8440 Series
Category	Stereo System
Language	English