Sharp 65480, Service Manual

Page: 59 / 90

59
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YES
NO
YES
NO
YES
NO
YES
NO
YES
NO
YES
NO
YES
YES
NO
YES
YES
NO
YES
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YES
NO
YES
NO
Data dropout (relating to gray scale)
Noise is caused to the moving picture with the QS drive on.
The backlight does not go on.
The whole screen is whitish (LCD power supply).
Set PATTERN1 PATTERN1 on the adjustment process menu
to "2". Is the gray scale pattern displayed correctly?
Set PATTERN1 PATTERN3 on the adjustment process menu
to "1". Is the gray scale pattern displayed correctly?
Is OSTEMP.AD on Page 1 of the process adjustment mode set at
255?
Is the harness connected correctly between the inverter GND
PWB and LCD control PWB?
Is any of the fuses in the power supply unit blown?
Is power supplied to the inverter PWB?
Connect the harness correctly or replace it.
Set PATTERN1 PATTERN3 on the adjustment process menu
to "1". Is the gray scale pattern displayed correctly?
Disconnect the FPC from SC4651 and SC4652. (To protect the
panel against damage)
Check the power supply voltage supplied to the panel (check at
SC4651 and SC4652).
Is the harness connected correctly between the PWBs (power
unit, inverter PWB, inverter GND PWB and LCD control PWB)?
Check the connector and inverter circuit of each fluorescent lamp.
Check the peripheral circuits of IC4501.
Check the video signal circuit.
Is the input voltage at pin (62) of IC2004 (microprocessor) 5V?
The thermistor on the inverter GND PWB is faulty.
Set PATTERN1 PATTERN3 on the adjustment process menu
to "5". Is the test pattern displayed correctly at intervals of one
dot?
Set PATTERN1 PATTERN3 on the adjustment process menu
to "4". Is the test pattern displayed correctly at intervals of one
dot?
Check the connection between SC4651 and SC4652 and check
the peripheral circuits of IC4501.
Check IC4701 and IC4901 and their peripheral circuits.
Connect the harness correctly or replace it.
Pin (62) of IC2004 (microprocessor) is faulty.
Check the inverter circuit located downstream from the blown
Is the control signal applied to P7705 of LCD Control PWB?
Check IC4702, IC4902 and their peripheral circuits.
Check the line between IC4701 and IC4501.
Check the peripheral circuits of IC4602.
Check the line between IC4901 and IC4501.
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TROUBLE SHOOTING TABLE (Continued)