Sharp LC-32LE40E - Chapter 4. Troubleshooting Table [1] Troubleshooting Table

LC-32LE40E-LC-42LE40E
41
CHAPTER 4. TROUBLESHOOTING TABLE
[1] TROUBLESHOOTING TABLE
Power unit operation check.
↓
LINE_FILTER_UNIT: ↓ YES
POWER_UNIT
↓YES
↓YES
↓YES
The sound is not emitted from the speaker though the picture has come out.
↓
No sound output in all modes?
TERMINAL 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
p
ower.
Is F9901/F9902 normal?
NO
LINE_FILTER_UNIT:
Isn't NR9901,NR9902,IC9901,L9901,L9902(32”)/L9903(42”),etc.
out of order? Moreover, whether the short-circuit with the
circumference circuit is checked.
POWER_UNIT:
BD9901, FB9901, (FB9902, FB9906, D9101)(32”)/(FB902,
FB9801, D9801)(42”) etc. out of order? Moreover, whether the
short-circuit with the circumference circuit is checked.
Is B+_main(32”)/B1+(42”) output? (Set the main power SW to ON.)
Does the PFC circuit operate normally?
The circuit around the protection circuit etc. is checked.
NO
Is a voltage of +5.2V applied to pin (2,3) of connector
(CN9304(32”)/CN907(42”))?
(Set the main power SW to ON.)
Does the switching circuit operate normally?
Check circuit around the primary side (IC9301, T9301,
D9303(32”)/D9307(42”),etc.), the secondary side ((D9302,
L9301, ZD9316)(32”)/(D9308, L9304, ZD9103(42”), etc.), and
the protection circuit.
NO
Are 12 and 24V output as for the power on/off switch when it is on?
NO
Does the inverter circuit operate normally?
Check circuit around the primary side (IC9103, T9101, Q9101,
etc.)(32”)/(IC9101, T9101, Q9101, Q9102)(42”), the secondary
side ((IC9101, D9102, D9103)(32”)/(IC9302, D9115,
D9116)(42”), etc.), and the protection circuit.
Is the audio signal output of IC U401 normal?
NO
Check IC U401 and its peripheral circuits.
Is audio signal input to pin (15/20/21/22) of IC U602 (AMP)?
NO
Check the line between IC U401 and IC U602.
Is MUTE circuit [AMP_MUTE_LINE, POWERUP_LINE] normal?
Is the audio signal output of pin (1,2) (R) and pin (3,4) (L) of
CN601(AOUDIO-CONNECTOR) normal?
NO
Check the AMP_MUTE_LINE and POWERUP_LINE. (Q652,
Q653 etc.)
NO
Check IC U602 and its peripheral circuits.
Check Speaker (right and left) and wire harness.