when i first got this tv it turn on then off. when i openned it found that the backlight wirers were shorted out and the heat spots by the diodes i test the diodes they were good and fix the wires. now the tv worked but there was a loud squealing that would go away in 15 minutes. i thank it was coming from the transformer on the small power board. the tv work like this for two weeks until i took out the power boards and when i put them back in now the tv turns on then off again.
emerson lc320em82
Collapse
X
-
Re: emerson lc320em82
I've got a sylvania LC320SS9 in my basement with a broken screen. The power supply is roughly the same as yours. If i unplug one the bulbs the tv will turn on with the backlight for 2 seconds then shut back off to standby. So your issue is either a bad bulb or one of the transformers.
You can check the transformers with your multimeter in the OHM setting. Unplug each bulb and put the probe on the 2 pins on the power supply's ccfl connector. Post your results.Comment
-
Re: emerson lc320em82
Could be a bad cfl, or failing caps on the psu.
I would bet on inverter side of it.Do NOT touch heatsinks when testing for voltages as they may be LIVE!Comment
-
Re: emerson lc320em82
Mr Bill beat me to it, your psu is probably sensing that summat is not right so is switching off, i had a similar problem with a tv i bought, took the inverter board out, seen no problem, unplugged the cfls, plugged them back in, and hey presto its alive, been watchin tv on it for over 2-3 month.Do NOT touch heatsinks when testing for voltages as they may be LIVE!Comment
-
Re: emerson lc320em82
This might be another issue we may have to address after we solve your shutdown issue. When you repaired the wires was is because they were melted or cut? Does the noise specificly come from T2 if that bulb is plugged in?Comment
-
Re: emerson lc320em82
(t2) makes more noise than the other transformers but it sill light up its backlight and all the backlights work. t4 was the the transformer that the wires melted and shorted together but when i fix that the tv work for the two weeks untail i remore the power boards to test them and when i put them back in the tv did workComment
-
Re: emerson lc320em82
Maybe check the solder joints on the transformers. If you had a spare bulb i would plug it into T2 and see if the backlight would stay on. You might be able to swap T1 & T2 bulb connectors and see if the noise moves to the other transformer. It looks like from your pictures there is enough slack.Comment
Related Topics
Collapse
-
by DvsrHi. I need help from wiser guys. I am amateur in electronics and can't figure this out by myself.
I bought faulty speakers, M-Audio AV40's. Other speaker has all the electronics in it and the other speaker is just passive one powered by the other speaker's amp. Original problem with the speakers was loud buzzing. I figured out that there is something wrong with the capacitors. I went ahead and replaced every electrolytic capacitor on the PCB. The caps are good quality and have the same values as the original ones.
After replacing the caps I started testing out the speaker. It seemed...4 Photos-
Channel: Troubleshooting Audio Equipment
09-10-2025, 10:20 AM -
-
by caspianDear members,
I have a linear variable power supply with unknown brand name that I used for voltage injection.
Then it failed. I discovered that its transistors (Q1 and Q2) are shorted.
In addition, I discovered that its zener diodes are defective.
I can replace the burned transistors.
But I do not know the model of the zener diodes. the model number is not marked on the zener diodes.
Therefore, I cannot replace the zener diodes.
I do not want to test the zener diodes in a test circuit to discover their model or value.
no schematics are available... -
Hi,
Found an Funai 32FL553P/10 TV on sale for cheap listed as broken, so I decided to give a shot at reparing this.
State I got it in:
Squealing from the PSU
After logo I get a blank screen
After 10 seconds of having a blank display w/ backlight the TV dies
Give it 7-10ish seconds again and it starts to bootloop.
What I did so far:
Replaced all the caps on the PSU (apart from primaries, they were fine and none at hand)
Checked all voltage rails:
5VSB - 4.8V
AMP+13V - 14.4V
13V - 12.98V (in manual 12V)... -
Hi folks. As the title says, I was doing a port replacement on a Lenovo Thinkpad T480s and in the process of post-solder cleaning, I somehow knocked off 2 or 3 diodes (i think they are diodes) near the main usb-c. I can't seem to find what kind of a diode is that. I know it's ultra tiny and just has a letter "G" on it. Would someone maybe have a proper schematic for the t480s model? I can only find the non-s one and it's quite different to the "s". Would love to figure out what component that is.
Thanks in advance!... -
by Fontana
- g´day! I have a samsung 22" tv monitor to fix. power supply model bn44-00505A. some stuff blown up on the primary, according to research something typical on this model. secondary seems ok. writings on the board say in outputs a5v (standby), b5v (switched) both on the lower 3 diodes on the picture, vamp and b13v (12.8v, both are the linked at the connector that goes to the main board) my question is, are both the upper diodes for 13v? I believe so but wanted to make sure before injecting voltage there to test. I injected 5v on the lower side and standby circuit is working fine
- if
12-18-2023, 05:45 AM - g´day! I have a samsung 22" tv monitor to fix. power supply model bn44-00505A. some stuff blown up on the primary, according to research something typical on this model. secondary seems ok. writings on the board say in outputs a5v (standby), b5v (switched) both on the lower 3 diodes on the picture, vamp and b13v (12.8v, both are the linked at the connector that goes to the main board) my question is, are both the upper diodes for 13v? I believe so but wanted to make sure before injecting voltage there to test. I injected 5v on the lower side and standby circuit is working fine
- Loading...
- No more items.
Comment