Backlight Failure To Light Up - Sharp LC-19D1E/S-BK/WH Service Manual

19INV
Do all the fluorescent tubes light up?
YES
Remove CN2 connector of POWER
unit. When you input 3.3V to pin(9) of
CN2 connector , check whether
UR12V are outputted to pin(13) to
(15).
YES
Check whether AC voltage
(800VRMS) is output to connector
CN7502 and CN7503.
YES
Check whether LAMP_ON/OFF and a
LAMP_CTL signal are normally input-
ted into pin(6)(7) of connector CN2.
YES
Exchange the power supply units.
LCD failure
LCD failure

Backlight failure to light up

NO Check the individual fluorescent
tubes for light-up failure.
NO Exchange the power supply units.
Does a single or several vertical
stripes appear on the LCD screen?
Does a single or several horizontal
stripes appear on the LCD screen?
Do luminescent or black dots appear
on the screen?
Is the on-screen image rippling or
distorted?
The backlight functions.
Does not the image come out in the
LCD screen (screen black)?
Does the entire LCD screen look
whitish all over?
Does the QS drive function?
Are there data bit drop-outs?
(No solution even when turning on
and off the QS drive)
Is the gamma correction as
specified?
4 – 23
LC-19D1E/S-BK/WH
YES Replace any defective fluorescent
tube (s) with new one (s).
Replace the LCD panel.
Replace the IC9201 (RSDS-transmit-
ter).