Sharp LC-22LE320 Service Manual page 77

26" TROUBLESHOOTING TABLE
↓
Are the power cord and harness in the unit properly connected?
↓ YES
LINE_FILTER_UNIT:
Is F901 F902 normal?
↓YES
POWER_UNIT
Is BD901 (+320V) output?
↓YES
Is a voltage of +5.3V applied to pin (12,13) of connector (CN905)?
↓YES
Is a voltage of +24V applied to pin (1,2,3,4,5) of connector
(CN903)?
↓YES
Is a voltage of +24V applied to pin (9,10) of connector (CN905)?
Is a voltage of +12V applied to pin (4,5) of connector (CN905)?
LC-19LE320, LC-22LE320, LC-26LE320, LC-32LE320, LC-37LE320, LC-42LE320
Power unit operation check.
↓YES
2008-03-14
NO
Connect the power cord and harness properly, and turn on the
power.
LINE_FILTER_UNIT:
Isn't C914, RV901, RV902, L903, L905, C937, C900, C920, etc.
out of order? Moreover, whether the short-circuit with the
NO
circumference circuit is checked.
NO
Does the circuit operate normally?
Check circuit around (BD901, Q905, ZD906, IC901, D902 etc ).
NO
Does the switching circuit operate normally?
Check circuit around the primary side (T901, ZD906, D902,
D905, Q905, D904, IC901, Q901, ZD904 etc.), the secondary
side (D903, L902, C911 etc.), the DC_DET circuit (IC902,
ZD903, IC903, IC901, etc.), and the protection circuit.
Does the inverter circuit operate normally?
NO
Check circuit around (D901, L901, C908, Q903, ZD902 etc.), and
the protection circuit.
Does the inverter circuit operate normally?
NO
Check circuit around (D983, C956, FB985, etc.), and the
protection circuit.
Does the inverter circuit operate normally?
NO
Check circuit around (D985, IC905, D907, L904, C927 etc.), and
the protection circuit.
77