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Service Manual of TFT-700
Service Manual of TFT-700
Damageable Parts
CSC2600, B1203,CPU, High-Voltage fuse N25,High-Voltage Circuit Audion, Transformer,
On/Off switch, Flat Cable, LCD Panel
1. Scenario: No sound, No picture, No light
Whether Power LED is working
in RED
YES
Press POWER button and test pin 29 of
CPU, see if voltage change from 05V or
50V
NO
Test whether CPU 5V
power supply is OK
YES NO Is Button input pin
voltage right?
NO
Is CPU C1815,B1203 and
Is IC M61260pin32 voltage OK? back power circuit shorted? NO YES Change CPU
YES Test circuit of CPU pin 22 Original Cause
to IC M61260 pin 32
NO NO YES Change B1203
Is IC M6260pin12 voltage right? C1815 to avoid short
Is all circuit coming out from power supply voltage right?
NO YES IC M61260 Bad
Is IC M61260 pin 12 power supply circuit OK? YES NO
Repair Power supply or relative circuit.
NO NO Change High-voltage circuit
Is there High - Voltage output? Check High-Voltage circuit N25
broken? audion or high-voltage transformer
YES
Change LCD Panel
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Service Manual of TFT-700
2. Scenario: Abnormal Color
Is IC M61260 pin14,15,16 output voltage OK?
NO Is IC M61260 has power supply?
YES
Is IC CSC2600 Pin6,8,9,29,32,35 voltage OK?
YES
Change IC M61260
NO
YES Change defect parts in loop
circuit.
Change Circuit cable of
LCD Panel
NO
Is circuit around IC CSC2600 OK?
YES
Change IC CSC2600
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Service Manual of TFT-700
3. Scenario: No Sound, with Light, Black Screen
Is power supply to IC M61260 pin
3,4,12,39,40 alright?
NO Check Power Supply
YES
Is IC M61260pin 24,26,27,34 working alright?
NO
Is CPU circuit and relative circuit
around IC M61260 pin 34 alright?
YES
Is voltage of IC M61260pin 14,15,16 alright?
NO Change IC M61260
YES
Is voltage of IC CSC2600pin 6,8,9 alright?
NO
Check circuit around IC CSC2600
YES
Change LCD Panel
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Service Manual of TFT-700
4. Scenario: Horizontal and Vertical Not in Sync
Is IC M61260+5V +8Vwell powered?
NO Repair Power Supply
YES
Is relative circuit around IC M61260
pin 5, 11 alright?
NO
Check relative circuit around
pin 5,11
YES
H/V Sync
Check circuit around IC 4001
circuit
YES
Check LCD Panel pin 6 alright?
YES
Change Flat Cable
NO
Change LCD Panel
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Service Manual of TFT-700
5. Scenario: White Light
Check switches power +5V +8V +17V