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Only for training and service purposes.
ONE POINT REPAIR GUIDE
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 pickup module in MD doesn’t work. This step is for checking the laser focusing actuator.
5-5. LASER FOCUSING ACTUATOR
5-5-1. Solution
Replace IC401 or IC400 on MAIN board.
5-5-2. How to troubleshoot (Countermeasure)
The focusing actuator makes the laser beam keep a regular interval with the surface of a CD disc.
1) Check the FDO signal from pin13 of IC401.
If no signal, check 3.3 V(RF) and X400.
2) Check F- & F+ from IC400 to CN400 for driving the focusing actuator.
If no signal, check M_5V for IC400.
3) Check if the FFC cable is solidly connected between CN400 and MD.
4) Check the MD.
If the pickup module has any trouble, it can not move the laser beam on the top or bottom side.
Please check the function after changing another MD.
5-5-3. Service hint (Any picture / Remark)
< Waveform of F±
for driving FOCUSING actuator >
mT Gju[W[
mRGGju[W[
< MAIN board top view >
F-
F-
pin18 to CN400
pin18 to CN400
F+
F+
pin15 to CN400
pin15 to CN400
CN400
CN400