4. TROUBLE SHOOTING
- 68 -
START
Check Battery Voltage
> 3.35V ?
Push power-on key
And check the level change
of PWRKEY
Check the voltage of
The LDO outputs at U101
Logic level at KEYON of U101
= HIGH
Does it work properly?
THE PHONE WILL
POWER ON.
Charge or Change Battery
Check the contact of power key
Or dome-switch
Replace U101
VCORE=1.8V VVCXO=2.75V
VMEM=2.8V VRTC=1.8V
VEXT=2.8V VSIM=2.85V (when sim card is inserted)
VABB=2.75V VMIC=2.5V
Re-download software
The power-on procedure is
Completed. The problem may
be elsewhere.
Does it work properly?
Replace the main board
YES
YES
YES
YES
YES
NO
NO
NO
NO
NO
NO
Checking Flow
Summary of Contents for KG320
Page 1: ...Date May 2006 Issue 1 0 Service Manual Model KG320 Service Manual KG320 ...
Page 3: ... 4 ...
Page 20: ...3 TECHNICAL BRIEF 21 Figure 3 5 SKY77328 FUNCTIONAL BLOCK DIAGRAM ...
Page 39: ...3 TECHNICAL BRIEF 40 3 7 CAMERA IC AIT811T U103 Figure 3 18 AIT811T APPLICATION BLOCKDIAGRAM ...
Page 41: ...3 TECHNICAL BRIEF 42 3 8 MIDI IC YMU787 U202 Figure 3 20 YMU787 BLOCKDIAGRAM ...
Page 72: ...4 TROUBLE SHOOTING 73 4 6 LCD Trouble AIT811T EMI FILTER CN102 TEST POINT Figure 4 6 ...
Page 90: ...4 TROUBLE SHOOTING 91 4 14 Camera and Flash Trouble Camera Module U201 CN202 Figure 4 17 ...
Page 99: ... 100 ...
Page 107: ... 108 8 PCB LAYOUT ...
Page 108: ... 109 8 PCB LAYOUT ...
Page 109: ... 110 8 PCB LAYOUT ...
Page 110: ... 111 8 PCB LAYOUT ...
Page 111: ... 112 8 PCB LAYOUT ...
Page 112: ... 113 8 PCB LAYOUT ...
Page 113: ... 114 ...
Page 121: ...10 STAND ALONE TEST 122 Figure 10 2 HW test setting Figure 10 3 Ramping profile ...
Page 127: ... 128 ...
Page 129: ... 130 ...
Page 147: ...Note ...
Page 148: ...Note ...