Samsung LN40B500P3F power on issue

[jonesfamily]

Re: Samsung LN40B500P3F power on issue

ok thanks again

[budm]

Re: Samsung LN40B500P3F power on issue

OK, set the meter to OHM mode at 200 scale (we are looking for low resistance reading due to shorted out components).
So take the reading between
1 & 2 =
1 & 3 =
1 & 4 =
2 & 3 =
2 & 4 =
3 & 4 =

[jonesfamily]

Re: Samsung LN40B500P3F power on issue

Ok i checked it and nothing changes between them so im guessing that means no open curcuit or short between them right?

[jonesfamily]

Re: Samsung LN40B500P3F power on issue

I will try to keep checking my posts as often as possible so i can get right back to you with answers to try and make it easier and not to take up too much of your time, i appreciate the help alot and im sure you have better things to do, thanks again

[vinceroger69]

Re: Samsung LN40B500P3F power on issue

can you post the readings up so we can double check them.

[budm]

Re: Samsung LN40B500P3F power on issue

I expected it to shorted in either between ~ and ~ (input side of the Bridge), or between the + and - for the output side, amd also between the internal of the bridge itself. We need to see the readings and the Ohm scale you are using.

[jonesfamily]

Re: Samsung LN40B500P3F power on issue

there were no readings, when i touch the probes together the reading is 00.0 but when i tested between all the spots numbered on the board nothing happened it didnt show anything?

[jonesfamily]

Re: Samsung LN40B500P3F power on issue

ok i will get a picture and show you

[budm]

Re: Samsung LN40B500P3F power on issue

OK, lets try this, get yourself a 75W light bulb that can be put into lamp socket with two wires coming out, then attach each wire of the lamp to each fuse holder clip ( you are basically use the lamp inplace of the fuse). Plug the TV into the out let, if there is big shorted in the TV, the lamp will light up brightly. If not the lamp may be cycling on/off.

[jonesfamily]

Re: Samsung LN40B500P3F power on issue

Let me know if im doing something wrong

[budm]

Re: Samsung LN40B500P3F power on issue

You did it correctly, thanks for the good clear pictures. Try the lamp trick next. Just to be sure, you did use the same size rating fuse?

[jonesfamily]

Re: Samsung LN40B500P3F power on issue

yes i used the exact same size fuse, but it was from radio shack and it was a slow blow? and it was a clear one not a white one like what was in there but the guy said it was the same rating and would work fine?

[jonesfamily]

Re: Samsung LN40B500P3F power on issue

I am going to get a small lamp and a 75w bulb and do what you said i will let you
know the results, Im guessing that means put the tv back together first right?

[vinceroger69]

Re: Samsung LN40B500P3F power on issue

some good clear pictures thanks and yes assemble tv back up and remove fuse put bulb leads across fuse holder and turn the tv on tell us what the light does ie brightness etc.

[jonesfamily]

Re: Samsung LN40B500P3F power on issue

I did the test and the 75w bulb turned really bright right away so im ready for the next step

[budm]

Re: Samsung LN40B500P3F power on issue

OK, you still have dead short circuits which some how did not show up when you test the bridge rectifier test points which should have shown the shorts if it was in the input side or at the output side. I will have to tell you to remove certain parts till we eliminate the shorts.

[jonesfamily]

Re: Samsung LN40B500P3F power on issue

ok just let me know whatever you need me to do, thanks again

[budm]

Re: Samsung LN40B500P3F power on issue

OK, put in the new fuse (3.1A fuse) and remove the main AC fuse, then put the lamp on that fuse clip instead.
Then lift one leg of the inductor BD901 (on page 2 of the diagram). Then use the Ohm meter in 200 Ohm scale and check the resistance between one end (either end of this new fuse) of the 3.15A fuse and the negative leg of any of the two large cap to see what you get.

[jonesfamily]

Re: Samsung LN40B500P3F power on issue

ok i will try that either tonight or in the morning and let you know the results right away, thanks

[alheyne]

Re: Samsung LN40B500P3F power on issue

OK, set the meter to OHM mode at 200 scale (we are looking for low resistance reading due to shorted out components).
So take the reading between
1 & 2 =
1 & 3 =
1 & 4 =
2 & 3 =
2 & 4 =
3 & 4 =

I have the same board & tv, only mine just flashes a few times on and off.
I get readings on everything in this process except 2&3.... I get nothing on 2 and 3. any thoughts would be appreciated.