3-2
ELECTRICAL TROUBLESHOOTING GUIDE
1. SMPS BOARD
YES
YES
YES
YES
YES
No power.
Replace SMPS board.
Connect the open line.
Replace F901.
Check SMPS second part lines short.
Check 3.7 V lines short.
Replace PC951, PC972, IC901.
Check BD901 “+”
to “-” Pin impedance .
Check MAIN or AMP board short.
Replace PC972, IC902’s components.
Check around IC901’s components
(Short, Open).
Low impedance:
Replace IC901, BD901.
NO
NO
NO
NO
NO
Check the AC
line pattern.
Check fuse F901.
Check C963
voltage (5.6 V).
Check C978
voltage (3.9 V).
Check IC901
Vcc voltage (10 V ~ 30 V).
Summary of Contents for MDT505
Page 11: ...2 2 MEMO ...
Page 15: ...2 9 2 10 MEMO MEMO ...
Page 16: ...2 11 4 SPEAKER SECTION 4 1 FRONT SPEAKER MDS505V A60 ...
Page 17: ...2 12 4 2 PASSIVE SUBWOOFER MDS505W A90 ...
Page 19: ...2 14 MEMO ...
Page 37: ...3 18 3 VIDEO PART 1 100 FULL COLOR BAR CVBS_I Y Pb Pr 8 9 10 11 8 10 9 11 ...
Page 38: ...3 19 4 VIDEO PART 2 100 FULL COLOR BAR CVBS COMP_Y COMP_Pb COMP_Pr 12 14 13 15 12 13 14 15 ...
Page 45: ...3 26 40 42 41 11 SPINDLE CONTROL WAVEFORMS NO DISC CONDITION FIG 11 1 42 41 40 SPinD SP SP ...
Page 47: ...3 28 MEMO ...
Page 64: ...3 61 3 62 PRINTED CIRCUIT BOARD DIAGRAMS 1 MAIN P C BOARD TOP VIEW ...
Page 65: ...3 63 3 64 MAIN P C BOARD BOTTOM VIEW ...
Page 67: ...3 FRONT VFD USB MIC VOLUME P C BOARD 3 67 3 68 ...
Page 69: ...3 71 3 72 MEMO MEMO ...