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3-14
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 pickup module in MD doesn’t work. This step is for checking the
LASER TRACKING ACTUATOR.
5-4. LASER TRACKING ACTUATOR
5-5-1. Solution
Please check and replace IC407, IC408 on MAIN board.
5-4-2. 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 Pin22 of IC407.
If no signal, check 3.3 V(RF) and X400.
2) Check TR- & TR+ from IC408 to CN404 for driving the tracking actuator.
If no signal, check +1.8 V and +5 V for IC408.
3) Check if the FFC cable is solidly connected between CN404 and MD.
4) Check the MD.
If the pick-up 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.
5-4-3. Service hint (Any picture / Remark)
{yRGGju[W[
{yT Gju[W[
ju[W[
{yR
X]GGju[W[
{yT
X^GGju[W[
< Waveform of TR±
for driving TRACKING actuator >
< Signal check point >
Summary of Contents for CM8440
Page 15: ...MEMO 2 2 ...
Page 19: ...A60L 4 SPEAKER SECTION 4 1 FRONT SPEAKER CMS8440F LEFT SPEAKER ...
Page 20: ...A60R FRONT SPEAKER CMS8440F RIGHT SPEAKER ...
Page 21: ...A90 4 2 SUBWOOFER SPEAKER CMS8440W ...
Page 73: ...3 65 3 66 PRINTED CIRCUIT BOARD DIAGRAMS 1 SMPS P C BOARD TOP VIEW ...
Page 74: ...3 67 3 68 SMPS P C BOARD BOTTOM VIEW ...
Page 75: ...3 69 3 70 2 MAIN P C BOARD TOP VIEW ...
Page 76: ...3 71 3 72 MAIN P C BOARD BOTTOM VIEW ...
Page 77: ...3 73 3 74 3 FRONT VOLUME P C BOARD ...
Page 78: ...3 75 3 76 4 MIC PORTABLE P C BOARD MEMO ...
Page 79: ...3 77 3 78 MEMO MEMO ...