4. TROUBLE SHOOTING
- 123 -
Figure 4-86.
START
Does the audio
profile of the phone
change to the
earphone mode?
Check the voltage Level
CN400.7 = Low?
Replace U100 or
Change Board
Re-solder CN400 or Change
another Ear-Mic set and Try again
Key
Mic
Earphone
Go to Key
Trouble section
Go to MIC
Trouble section
Go to Speaker Trouble
Check the Level of
CN400.8~12 change,
when you press any keys
Resolder CN400
Resolder causal
component
(CN400, R408 etc.)
Check the signal
Level at AUX_MIC_P.
Is it about 1.2~1.5V DC
with a few tens mV AC?
Change another Ear-Mic set and Try again
Check the Level of
U402.C2 = High ?
No
Check the Signal, U404.A2
and U404.C2
No
Yes
Sound
Acoustic
Does waveform at
U100.J16 and U100.K16
fluctuate?
Replace U100 or
Change the board
Does waveform at
CN400.4 and CN400.5
fluctuate?
Resolder causal
component
(CN400, R408 etc.)
Check the Level of
U402.C2 = Low ?
No
Replace
R427
Replace
U402
Replace R427
Does waveform at
CN4100.4 and CN400.5
fluctuate?
Resolder causal
component
(CN400, R408 etc.)
Change another Ear-Mic set and Try again
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
No
No
No
No
No
CHECKING FLOW
Содержание KG920
Страница 3: ... 4 ...
Страница 48: ...3 TECHNICAL BRIEF 49 3 8 2 AFE Analog Front End Figure 3 22 ...
Страница 52: ...3 TECHNICAL BRIEF 53 3 8 5 MBGM01 5M CCD ISP Figure 3 25 ...
Страница 55: ...3 TECHNICAL BRIEF 56 3 8 6 MV8620 5M back end IC Multi Media Function Figure 3 26 ...
Страница 58: ...3 TECHNICAL BRIEF 59 3 9 MIDI IC YMU787 Figure 3 27 YMU787 BLOCKDIAGRAM ...
Страница 87: ...4 TROUBLE SHOOTING 88 Graph 4 8 BLUE RST Graph 4 9 DEBUG_TX RX Graph 4 10 PCM_SYNCS TX RX USC0 ...
Страница 96: ...4 TROUBLE SHOOTING 97 4 7 KEY backlight Trouble TEST POINT Q101 R122 Q101 LD101 LD119 Figure 4 38 Figure 4 39 ...
Страница 108: ...4 TROUBLE SHOOTING 109 CIRCUIT WAVEFORM Figure 4 59 Graph 4 11 Figure 4 60 Figure ...
Страница 109: ...4 TROUBLE SHOOTING 110 TEST POINT U602 FB602 U100 Q100 Q101 C113 C114 Figure 4 61 Figure 4 62 ...
Страница 111: ...Figure 4 65 Graph 4 12 4 TROUBLE SHOOTING 112 C102 C113 U101 Figure 4 66 C137 U103 TEST POINT WAVEFORM ...
Страница 112: ...4 TROUBLE SHOOTING 113 Figure 4 67 Figure 4 68 CIRCUIT ...
Страница 115: ...4 TROUBLE SHOOTING 116 WAVEFORM Graph 4 13 ...
Страница 139: ...6 BLOCK DIAGRAM 140 6 BLOCK DIAGRAM Figure 6 1 ...
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