Panasonic UF-5500 Service Manual page 184

UF-5500 / 4500
3. DEV DC
DEV BIAS
Is CHG REM signal (Pin5)
at a low level?
YES
Does the DEV CLK
signal (Pin4) turn ON/OFF
at 5.425kHz?
YES
Is the abnormal
detection signal (Pin2) 0V?
YES
Does pin1 of IC1
output signal?
YES
Is about 34kHz sine
wave observed at
the collector of Q3?
YES
Replace the Unit.
Check the connection between
NO
Main Board (Pin5 of CN505)
and HVPS unit (Pin5), and
check the Main Board itself.
Check the connection between
NO
Main Board (Pin4 of CN505)
and HVPS unit (Pin4), and
check the Main Board itself.
NO
Check if CHG is no-load
or short-circuited.
NO
Replace the IC1, and
check the peripheral parts.
NO
Replace the Q3, and check
the peripheral parts.
184