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5. Flow Chart of Troubleshooting and Circuit Diagrams
5-1 Power ON
Flow Chart of Troubleshooting and Circuit Diagrams
5-1
'POWER ON'does not work
Charge the Battery
Check the Battery Voltage
is more than 3.4V?
No
Yes
Yes
Check U300 and the path from +VBATT
to C305
The node
between D300 and C305 > 2.8 V ?
No
Yes
When the "END" key is pressed,
D314 pin 1> 3.4V ?
Replace the PBA
No
END
U301 pin 1, 2, 9 > 3.4V ?
Check the circuit related to U301
No
Yes
Check the initial operation
U301 pin 10 = 2.5 V ?
Check U301 and related circuit
No
Yes
Check for the clock signal at R103
Check the clock generation circuit
(related to U102 and Q100)
No
Yes
Yes
Summary of Contents for SGH-T400
Page 2: ...Samsung Electronics Co Ltd Printed in Korea 12 2002 Rev 1 0 GH68 03158A ELECTRONICS ...
Page 11: ...2 1 PCB Diagrams 2 PCB Diagrams 2 1 Main Top ...
Page 12: ...2 2 PCB Diagrams 2 2 Main Bottom ...
Page 26: ...Flow Chart of Troubleshooting and Circuit Diagrams 5 2 ...
Page 30: ...5 6 Flow Chart of Troubleshooting and Circuit Diagrams ...
Page 38: ...5 14 5 8 Receiver Part Flow Chart of Troubleshooting and Circuit Diagrams ...
Page 39: ...5 15 Flow Chart of Troubleshooting and Circuit Diagrams ...
Page 40: ...5 16 Flow Chart of Troubleshooting and Circuit Diagrams 5 9 Ring Indicator ...
Page 43: ...5 19 Flow Chart of Troubleshooting and Circuit Diagrams 5 12 GSM Receiver ...
Page 44: ...Flow Chart of Troubleshooting and Circuit Diagrams 5 20 5 13 GSM Transmitter ...
Page 45: ...5 21 Flow Chart of Troubleshooting and Circuit Diagrams 5 14 DCS Receiver ...
Page 46: ...Flow Chart of Troubleshooting and Circuit Diagrams 5 22 5 15 DCS Transmitter ...