Sharp LC-19LE430E, Service Manual

Page: 49 / 206

2008-03-14
LC-19LE430E/UK, LC-22LE430E/UK, LC-26LE430E/UK, LC-32LE430E/UK
49
32 ″ TROUBLESHOOTING TABLE
Power unit operation check.
↓
LINE_FILTER_UNIT:
↓ YES
POWER_UNIT
↓ YES
↓ YES
↓ YES
↓ YES
Are the power cord and harness in the unit properly connected?
NO
Connect the power cord and harness properly, and turn on the
power.
Is F9901 F9902 normal?
NO
LINE_FILTER_UNIT:
Isn't TH9901,L9901,L9902,FB9902,FB9901 out of order?
Moreover, whether the short-circuit with the circumference circuit
is checked.
Is C9803 (+395V) output? (Set the main power SW to ON.)
Does the PFC circuit operate normally?
(L9904, Q9801, D9811, IC9801 and etc. And, the circuit around
the protection circuit etc. is checked.)
NO
Is a voltage of +5V applied to pin (12,13) of connector (CN9002)?
(Set the main power SW to ON.) Does the switching circuit operate normally?
Check circuit around the primary side (T9301, IC9301, R9303,
D9311, etc.), the secondary side (D9301, ZD9311, L9301, etc.),
the AC_DET circuit (R9300, C9321, Q9313 etc.), and the
protection circuit.
NO
Are +12V and +24V output as for the power on/off switch when it is
on?
NO
Does the PFC circuit operate normally?
Check circuit around the primary side (R9142, T9111, Q9121,
Q9122, C9146 etc.), the secondary side (D9121, D9113, D9114,
D9111, D9112 etc.), and the protection circuit.
POWER_UNIT:
BD9901, FB9810, D9811, etc. out of order?
Moreover, whether the short-circuit with the circumference circuit
is checked.
Similarly, is +12V output as for the power on/off switch when it is
on? Check +12V circuit of D9111, D9112 etc.
NO