Lcd Related Symptoms - LG 15Z990 Series Service Manual

50
Malfunction Diagnosis and Related Parts

LCD Related Symptoms

CAUTION
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6
• When disassembling or replacing the LCD related parts, power off everything.
Malfunction Symptoms/Error Codes
The screen does not operate normally anymore.
LCD Backlight does not operate.
LCD is too dark.
LCD brightness cannot be adjusted.
LCD color is not proper.
LCD color contrast cannot be adjusted.
Broken fonts.
Cannot read what is on the LCD.
Wrong colors.
There is a horizontal or vertical line that was not
displayed on the LCD.
The power supply lamp is lit and during posting,
there is nothing on the LCD.
LGE Internal Use Only
Related Parts/Execution Order
a Press the start button and select [Windows System] > [Control
Panel] > [Hardware and Sound] > [Power Option] > [Setting
Change] and switch "Set PC to power saving mode" to "N/A" and
the check the problem.
b Check if in power saving mode. (Press the start button and select
[Windows System] > [Control Panel] > [Hardware and Sound] >
[Power Option] > [Setting Change] and switch "Set PC to power
saving mode" to "N/A" and the check the problem.)
• For laptop/tablet products, check the following items additionally.
a Check if it is in standby mode or max power saving mode. (Check
it in [Control Panel] > [Hardware and Sounds] > [Power Option]
> [System Setting].)
a LCD assembly
b System board
• For all in one products, check the following items additionally.
a Check if the BLU cable is connected properly.
b Check if the JOG cable is connected properly.
c JOG board
d MNT or MTV board
a Connect the LVDS again to the LCD assembly and the MNT or MTV
board.
b Replace the LVDS cable.
c LCD assembly
d System board
• For all in one products, check the following items additionally.
a Replace the 51pin Main-to-MNT cable or the stand body
assembly.
b MNT or MTV board
a LCD assembly (LCD panel damage)
a Reconnect the SODIMM memory to the connector.
b Check if the SODIMM memory is defective.
c LCD assembly
d System board
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