HP (Hewlett-Packard) LT4700 Flat Panel Television User Manual


 
HP High-Definition LCD TV Service Manual 83
Troubleshooting Tips
No Power
Check the power supply unit (PSU) – Is the PSU board defective?
Is the power cord connector grounded?
Check the cable between the PSU board and the main board.
Is the keypad/remote control power button working?
Is the power connector connected?
No Video
Is there an input source connected?
Is the LED on?
o Check the main board and panel cable connection.
o Is the power on?
o Is there battery in the remote control?
Keypad abnormal
Is the button working properly?
Check whether the LED is on.
Check module.
Check the cable and main board connection.
LED Display abnormal
If the LED is off/dark/abnormal – check main board or cable.
If the LED flickers – Power saving mode in VGA: push any key to restart.
Abnormal Display
Missing Line:
1. Check the cable between the main board and the control board
2. Check the panel board
Bright Dot/Dark Dot/Light Leakage/Mura (cloudiness)/Image Sticking/Brightness spot/Particles/Dot Defect –
Check panel
No Display – Check the main board, inverter board, and panel board.
Display Noise:
1. Check the cable between the main board and the control board.
2. Check the panel board.
Flicker/Image too dark – Check main board or inverter board, load default settings.
Gray value display – Check main board or panel cable, load default settings.
VGA no image – Check main board or D-sub cable: is NB switch to LCD monitor?