LG -T500 Service Manual page 69

(1) Checking Crystal Circuit
TEST POINT
Figure 4.2.1
CIRCUIT
X201 TSX-3225
Close to the 26MHz XTAL
4
3
GND2 HOT2
1 2
HOT1 GND1
VSIM_PWR
Connect GND plane directly
TP1
C231
0.1u
26MHz
TP1
Figure 4.2.2
LGE Internal Use Only
TP1_1 pin :
26MHz
X102
A4 USIF1_TXD_MTSR
UART_TX
B5
USIF1_RXD_MRST
UART_RX
A5
USIF1_RTS_N
BT_UART_RX
B4
USIF1_CTS_N
BT_UART_TX
K13
DPLUS
USB_DP
K14
DMINUS
USB_DM
B13
XOX
A13
XO
M10
VSIM
E2
SIM_DATA
SIM_IO
D1
SIM_CLK
SIM_CLK
D2
SIM_RST_N
SIM_RST
F1
MSD_CMD
MMCI_CMD
F3
MSD_D[0]
MMCI_DAT_0
F2
MSD_CLK
MMCI_CLK
G5
CHECKING FLOW
26 MHz O.K?
Yes
Crystal is OK.
See next page to check PLL
Circuit
WAVEFORM
Figure 4.2.3
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4. TROUBLE SHOOTING
No
Replace X201
TP1
Only for training and service purposes