Samsung SCR-3232, Service Manual

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7
n
Troubleshooting
+5V, +12V of CN700 is normally inputted after
connection of power cable?
X201, X301, X401 oscillate?
Check power short and power supply cable
connection state
After checking IC201 75pin, IC301 11pin,
IC401 88pin for power input, if normal, replace
X201, X301, X401.
IC308 2pin changes from 0V to 5V?
IC302 6pin changes from 0V to 5V?
IC308 3pin : 0V
→
5V check
Y
Y
N
N
N
N
N
Y
N
N
N
N
N
N
Disc insert
Replace IC308
Check R314, R330, R305 soldering
Check power input of corresponding
IC and replace it
N
Tray in/out? Refer to ‘Tray open/close’
Y
Y
Y
Laser diode on? Refer to ‘No laser diode on’
Y
Focus up/down? Refer to ‘No focus lock’
Y
Focus lock?
Y
Disc rotates? Refer to ‘No disc rotation’
Y
Pause state
v
Pause state : LED off as disc rotation state and continue 1 track jump
Y
Spindle lock?
Y
Pick up moves in at power on after moving
out?
Refer to ‘No sled operation’
IC302 3pin changes
from 5V to 0V when
power supplied?
Y
Check and
replace IC302
power
Y
Y
N
Is 3.3V supplied at IC202 4PIN?
IC202 surround circuits
R515, R514 check.
Is 3.3V sanctioned at IC201
DSPVCC terminal?
0V
→
5V changes at checking IC302 6pin
waveform while opening IC301 64pin and
IC401 9pin in turn
13
Equipments required at repair
1. Oscilloscope(100MHz and more) 2. PROBE for Oscilloscope(10:1)
3. PC(486 and more)
Verify the circuit of power unit and the first status(Plug-in the power cable without I/F cable and verify.)
TE signal at 1 track jump
N