50PC5D-UC, 50PC5DC-UC (CHASSIS:PA-73E) - LG TV Service Manual (repair manual). Page 20

Read LG 50PC5D-UC / 50PC5DC-UC (CHASSIS:PA-73E) Service Manual online

- 20 -
TROUBLESHOOTING GUIDE
Video doesn’t display
Check J5007 Pin3C
Can you see the normal waveform?
Check the input(Pin1 or Pin8) of AV
switch(IC5003). Pin1 is for video1,Pin8 is for
video 2.
Can you see the normal waveform?
Check the output(Pin56) of AV switch(IC5003).
Can you see the normal waveform?
Check the input(Pin1) of LPF(IC4006).
Can you see the normal waveform?
YES
YES
YES
NO
J5007 may have problem. Replace this Jack.
Check the output(Pin8) of LPF(IC4006).
Can you see the normal waveform?
YES
Check the input(PinH26) of BCM3550(IC4006).
Measure waveform at C1010 because it s more
easy to check.
Can you see the normal waveform?
YES
YES
NO
After checking the Power of AV switch you should
decide to replace AV switch or not.
NO
After checking the Power of AV switch you should
decide to replace AV switch or not.
NO
After checking the Power of LPF you should decide to
replace LPF  or not.
NO
After checking the Power of LPF you should decide to
replace LPF  or not.
This board has big problem because Main
chip(BCM3550) have some troubles.
After checking thoroughly all path once again, You
should decide to replace BCM3550 or not.
Page of 50
Display

Click on the first or last page to see other 50PC5D-UC / 50PC5DC-UC (CHASSIS:PA-73E) service manuals if exist.