Samsung SCH-3500 series Service Manual page 34

8-1-2 Abnormal initial operation (Normal +3.0V voltage source)
Press PWR Key
TCXO CLK
applied to U501 pin 35/
U103 pin 36?
TCXO CLK
signal outputted from
U103 pin 37?
RAM-CS signal outputted
from U100 pin 92?
CHIP X 8 CLK
signal outputted from
U103 pin 38?
Normal initial
display on LCD?
NO
YES
NO
YES
NO
YES
NO
YES
NO
LED on?
YES
NO
YES
END
SAMSUNG Proprietary-Contents may change without notice
Check VCTCXO output.
Check U103 and its neighboring
circuits. Replace if required.
Check MSM board, U100 pins 93-96,
98-105, 107-117, 119-126, and
128-132. Replace if required.
Check 'H' level input from
U103 pin38.
Check the LED and its neighboring
circuits. Replace if required.
Check the LCD pins and its neighboring
circuits. Replace if required.
8-2
Trouble Shooting