2. SYSTEM circuit
11
TROUBLESHOOTING
No Booting
VFD ON/OFF
NO
Check +6V EVER (Pin 9 of P503)
NO
Check POWER
NO
Replace Q108 &Q109
NO
Check FRONT
Reset IC
Pin 3 of IC110
High>Low>High
NO
Replace IC110
MICOM Crystal
Check whether
X105(16MHz) oscillates
NO
Replace X105
MICOM (IC107)
Check SDA(Pin 60)&SCL(Pin 61)
NO
Replace IC107
EEPROM(IC103)
Check SDA(Pin 5)& SCL(Pin 6)
NO
Replace IC103
Crystal
Check whether
X602(27MHz)Pin 5 oscillates
NO
Replace X602
Level Shifter
Check SDA(Q108) & SCL(Q109)
NO
Check whethet Q108 &
Q109 are working
YES
YES
YES
YES
YES
YES
YES
Replace Board( IC601 bad soldering)
1. NO BOOTING
Summary of Contents for DHD-4000D
Page 30: ...29 BLOCK DIAGRAM VIDEO BLOCK ...
Page 32: ...31 BLOCK DIAGRAM TUNER BLOCK ...
Page 40: ...39 SCHEMATIC DIAGRAM ...
Page 44: ...43 SCHEMATIC DIAGRAM SCHEMATIC DIAGRAM ...
Page 45: ...44 COMPONENTS LOCATION GUIDE ON PCB BOTTOM VIEW ...
Page 49: ......
Page 66: ...686 AHYEON DONG MAPO GU SEOUL KOREA C P O BOX 8003 SEOUL KOREA DAEWOO ELECTRONICS Corp ...