Operation Of Md - LG OK99 Service Manual

5. NO OPERATION OF MD
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 spindle motor among them.
5-1. SPINDLE MOTOR
5-1-1. Solution
Replace IC401 or IC400 on MAIN board.
5-1-2. How to troubleshoot (Countermeasure)
1) Check the SPDO signal from pin16 of IC401.
 If no signal, check DVCC_3.3V(RF) and X400.
2) Check the SP- & SP+ from IC400 to CN401 for driving SPINDLE motor. It is about 3.6 Vp-p.
 If no signal, check M_5V for IC400.
3) Check if the FFC cable is solidly connected between CN401 and MD.
4) Check the MD.
 If the spindle motor is short-circuit or has any trouble, it can not rotate CD discs.
Please check the function after changing another MD.
5-1-3. Service hint (Any picture / Remark)
< Waveform of SP- & SP+
for driving SPINDLE motor >
ONE POINT REPAIR GUIDE
SP+ SP+
pin6 to CN401 pin6 to CN401
SP- SP-
pin8 to CN401 pin8 to CN401
< MAIN board top view >
IC400 IC400
< MAIN board bottom view >
3-10
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CN401 CN401
Only for training and service purposes.