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3-17
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 tracking actuator.
9-4. LASER TRACKING ACTUATOR
9-4-1. Solution
Replace IC401 or IC400 on MAIN board.
9-4-2. How to troubleshoot (Countermeasure)
The tracking actuator makes the laser beam be positioned in the center of a track on CD disc.
1) Check the TRD signal from pin14 of IC401.
If no signal, check 3.3 V (RF) and X400.
2) Check TR- & TR+ from IC400 to CN400 for driving the tracking actuator.
If no signal, check +1.8 V and +5 V 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 left or right side.
Please check the function after changing another MD.
9-4-3. Service hint (Any picture / Remark)
< Waveform of TR±
for driving TRACKING actuator >
{yRGGju[W[
{yTGju[W[
< MAIN board top view >
TR-
TR-
pin17 of CN400
pin17 of CN400
TR+
TR+
pin16 of CN400
pin16 of CN400
Summary of Contents for CM9750
Page 15: ...2 2 ...
Page 19: ...4 SPEAKER SECTION A60L A60R ...
Page 75: ...3 71 3 72 PRINTED CIRCUIT BOARD DIAGRAMS 1 SMPS P C BOARD TOP VIEW ...
Page 77: ...3 75 3 76 2 MAIN P C BOARD TOP VIEW ...
Page 78: ...3 77 3 78 MAIN P C BOARD BOTTOM VIEW ...
Page 79: ...3 79 3 80 3 FRONT P C BOARD TOP VIEW ...
Page 80: ...3 81 3 82 FRONT P C BOARD BOTTOM VIEW ...
Page 81: ...3 83 3 84 4 FRONT_CTRL P C BOARD TOP VIEW BOTTOM VIEW ...