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HTP-SB300
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5. DIAGNOSIS
5.1 DIAGNOSIS FLOWCHART
Power ON
Is not there abnormality for FL
or LED display?
After removing the PWB(PCB)
Assy (FRONT/KEY), is the
output voltage (L101) of IC116
(BD9702T) +5 V?
NG
NG
After opening R299 (0 ohm 3216),
are the pins 1-3 of IC119 (SI9407)
shorted to GND?
Replace the IC119 (SI9407).
Check the D106 (SS15), and
replace it if it is defective.
Is the voltage between pin 1 and
2 of CN104 +4.3 V?
NG
NG
Check the voltages (+5 V)
of CP101-pin 3 (Vcc5) and
MOD101-pin 1 (5 V).
NG
OK
OK
OK
Check the D105 (SS15), and
replace it if it is defective.
Is the voltage between pin 3 and
4 of CN104 -30 V?
NG
Replace the IC115 (KIA278R33).
Is the voltage between pin 4 and
5 of CN104 +3.3 V?
NG
Replace the IC112 (IL1117-3.3V)
Replace the IC124
(IL1117-3.3).
Is the voltage of IC112
(IL1117-3.3) +3.3 V?
After having input HDMI with HDMI
_Function, is "HDMI Flag ON"
displayed in FL?
NG
Is the voltage of pin 16 (Vcc) of
IC105 (74LVC257) 2.4 V?
Check the output waveforms
(FB117,FB118,FB119) of IC105
(74LVC257).
NG
Check the ZD104 (2.4 V
Zener) and FB116(Bead).
NG
Is the voltage of pin 1 (A/B) of IC105
(74LVC257) High (+3.3 V)?
Check pin 70(R245) of IC113
(MICOM) is High.
Replace it when it is Low.
NG
Replace the PWB(PCB) Assy
(FRONT/KEY), then check it.
OK
OK
OK
OK
OK
OK
OK
OK
OK
Replace the PWB(PCB) Assy
(HDMI), the check it.
Check the connection of MICOM
communication port of PWB(PCB)
Assy(HDMI) and PWB(PCB) Assy
(MAIN). (CSSK_MAIN, SCDO_
MAIN, SCDI_MAIN,SUB_RESET,
SUBPDN, MAIN_IRQ, SUB_IRQ,
SUB_ON)
NG
OK
NG
Replace the PWB(PCB) Assy
(HDMI), the check it.
Check the waveforms of CP101-
pin 4(HDMI_SD0), pin 5(HDMI_
SD1), pin 8(HDMI_LRCK), pin 9
(HDMI_BCK), pin10(HDMI_MCLK).
Check audio output after HDMI input.
Note: Input signal uses Dolby 5.1ch
source.
NG
OK
Is the output voltage of
IC124 (IL1117-3.3)
+3.3 V?
Check the waveforms of IC106
(DA788_DSP)-pins 113 (R145)
and 116 (R146).
NG
Check it after opening
FB111 and FB129.
Check the existence of short-circuit
of DSP_3.3V and the DSP_1.2V in
the power supply section.
NG
NG
Replace the IC108 and
IC109 (IL1117-1.2).
OK
Is the output voltage of
IC108,109 (IL1117-1.2)
+1.2 V?
Check it after opening
FB112.
Check the existence of short-circuit
of DSP_1.2V in the power supply
section.
NG
NG
Replace the
IC104(CS8422).
OK
Check the XMCK wave-
form of pin 17(R164) of
IC106 (DA788_DSP).
Check the power supply
(FB105) of IC104 (CS8422).
Check the output waveform of
X101 (24.576 MHz).
NG
Check the DSP Firmware Version.
(SET STEREO KEY+RMC DIMMER KEY)
When "DSP:_:_ _:_ _" is
displayed, replace the IC110.
NG
NG
OK
OK
OK
TROUBLESHOOTING
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