Mulja tv repair portal

Equipment Repairs => LCD TV forum => Topic started by: WILLYAM1 on January 04, 2011,07:08:30

Title: lg-37lg31rc
Post by: WILLYAM1 on January 04, 2011,07:08:30

HI to all.
tv works fine but when turn it off by remot or stby botton  and turn it on again power led is blue(ok) but no screen no backlight no sound.
no 24v no 12v no 16.5 only 5.2v notice that all volltage  inv on low (suld be 3.3 and alsopwm signal low0 when plug out the inverter main cabel voltage came back again(inv on  'pwm sig' bright....)but still no 24v no 12 no16.5 eroor signal rize to 3v shuld be ov.0.
anyone hade the same problem?.
wikllyam,1

Title: Re: lg-37lg31rc
Post by: WILLYAM1 on January 05, 2011,06:41:49

were is all the expert? daz? sparky? turnip?brainstorm? vladimir?and ...........willyam1.
when inverter is out p.s works i have all voltage have sound but when inverteris fitted back sometime  backlight wirks sometime it dosent and no output voltage from p.s no12 v no 24v no 16.5v .
not sure if problem in p.s or in inverter or main board.
help willyam1.

Title: Re: lg-37lg31rc
Post by: daz on January 05, 2011,09:53:26

hi willyam
i for one is very hungover, :73:   took 10 minutes for me to remember how to use a screw driver this morning,got lots of posts to catch up on but i will try to help, havent met this model before, post some pics of the three pcbs, it might jog my memory.
regards
daz

Title: Re: lg-37lg31rc
Post by: WILLYAM1 on January 05, 2011,14:15:46

thanks daz.
i will some photos tomorow.
wikllyam1

Title: Re: lg-37lg31rc
Post by: WILLYAM1 on January 06, 2011,07:03:48

here some photos
.

Title: Re: lg-37lg31rc
Post by: daz on January 06, 2011,08:28:32

hi willyam
haven’t seen this one yet so not going to be much help, but check the inverter does it use a bd9897fs if so I would change this first as they can give problems, also had problems with poorly fitted lg backlights intermittently arcing to the shielding at startup causing the set to go into fault mode, you will have to strip the panel down and check for burn marks near the ends of the tubes.(also check for loose tubes)
hope this is of some help
daz

Title: Re: lg-37lg31rc
Post by: WILLYAM1 on January 06, 2011,08:38:55

thanks daz i will check and keep you posted.
willyam1