LCD TV and Monitor basic troubleshooting guides

[budm]

Correct way to report the Voltage reading at the connector:
CN201 connector from Power Board to Main Board:
Pin__Label_____TV off volts__TV on volts
1____3.3V________3.33__________3.31
2____AC-DET______3.41__________3.39
3____PS-ON_______0.08__________3.28
4____12V-AU______0.60_________12.24
5____GND_________0.00__________0.00
6____GND_________0.00__________0.00
7____GND_________0.00__________0.00
8____12V REG_____0.56_________12.24
9____12V REG_____0.54_________12.24
10___BL-ERR______0.00__________3.26
11___LED-ON______0.00__________3.24
12___LED-BR______0.00__________0.82
13___NC__________0.00__________0.00
14___T2V T CON___0.04_________12.24
15___T CON_ON____0.00__________3.17

Thanks for splinke for making easy for us to help: https://www.badcaps.net/forum/showthread.php?t=70560

[wyl2p]

Hey all! I''m not sure if it's ok to ask some help from this thread or if i'm supposed to post a new thread. I'll go ahead and state my issue and just let me know if i'm doing something wrong lol.

Anyways, my Sony 46" KDL46V5100 just stopped working, as i was watching, it suddenly had like a faded blurring picture and just went black and no sound whatsoever. It's been like that since. So reading the LCD trouble shooting guide posted in the thread, it sounds like my main board needs to be replaced and wanted to see what you think.

Symptoms: No picture, no audio and no backlight. I also did the flashlight test and didn't see any images.

Troubleshot:
- Power supply board: I have my standby 3.3V and ON/OFF 3.3V, and the 15V & 12V going to main board. I also have 12V going to the TCon board.

Unsure about power supply:
- Dimmer(.49V), backlight on/off(1.15V), inv_err(2V), gnd, & barancer_err(0V), this connecter i measured at leads to the main board. I assume these voltages aren't correct and should be more?

- VCC(12V), FB(0), FB(0), GND, GND, LD(11.4), LD(11.4V), this connector leads to the inverter board. Are these voltages good or no good? I get 11.4V on LD and 0V on FB and i don't know what these are. The VCC 12V is there tho and that's what the board is marked at so that should be good.

I also checked the power supply fuse and that's good. So after reading the troubleshooting guide again, I'm thinking the main board. Please let me know what you think, thank you in advance!

[nader770]

Thank you

[budm]

LG 50LA6205 bad panel with taped off fixed by neilc6 and davi.p
https://www.badcaps.net/forum/showth...904#post851904

[budm]

Info about T-CON:
Info provided by http://tvrepairsolution.blogspot.com
http://tvrepairsolution.blogspot.com...l-rowgate.html

[budm]

AOZ9148 LED driver IC used in many Samsung LED power supply section.

[budm]

Samsung UN50H5203
https://www.badcaps.net/forum/showthread.php?t=72153
https://www.badcaps.net/forum/showthread.php?t=72173
This is related to LED driver topology such as the one using AOZ1948 IC.
Samsung boards BN44-00775A, BN44-00772A use that topology.

[elsherb]

Great job Bud M.
Very handy and informative guides.
Keep it up

[budm]

SONY LCD TV (I.E. Sony KDL-55EX700, Sony KDL-46EX710) 7-Blink code for temperature error. This can be fault direction, it can be due to problem in the HLR board.
https://www.badcaps.net/forum/showthread.php?t=46810
https://www.badcaps.net/forum/showth...ard#post706697

[budm]

TFT-LCD Production Process Explained: LG
https://www.lgblog.com.my/2014/10/15...ess-explained/

Understanding Today's LCD Screen Technology: Samsung
https://pid.samsungdisplay.com/en/le.../lcd-structure

[budm]

LG T-CON Training manual.

[budm]

Some interesting read about the TV display technology.
https://www.displaydaily.com/article...heir-tv-allies

[thoma]

http://televid-sib.ru/index.php?topi...9572#msg139572

TRAINING VESTEL 17MB 120
Registration required!

[budm]

Panasonic training material:
http://service.panasonic.ca/pcs/EXT_...circuit_v2.pdf

[eauyong]

Originally Posted by budm

Panasonic training material:
http://service.panasonic.ca/pcs/EXT_...circuit_v2.pdf

Thanks!

[thoma]

Panasonic Training LCD TV links
See Page 15
LCD TV and Monitor Basic Troubleshooting guides

[Lapy]

Many thanks

[euchoulis]

Great job ,guys. Happy new year.

[Nelsky22]

Please help.! What is the problem Sony 32bx320 with sound but no pictures

[budm]

Power supply output impedance.
http://powersupply.blogs.keysight.co...impedance.html

https://community.keysight.com/commu...c-power-supply

https://community.keysight.com/commu...haracteristics

https://community.keysight.com/exter...ulate-its.html