Re: LG 42lg30-UD... no picture
To update thread, I went ahead and purchased a mainboard from a seller on E-bay. It arrived today and I installed it. Set is working all looks good so far.
Thanks for the help!
stratos976
Member
Last Activity: 03-13-2015, 03:31 PM
Joined: 04-19-2014
Location: Mechanicsville, VA
-
Re: LG 42lg30-UD... no picture
What things or where would I need to check to see if the signal isn't being generated properly. That sounds like an internal board thing, but it may be something I could fix?Leave a comment:
-
Re: LG 42lg30-UD... no picture
Thanks, so next step would be to replace main board I assume.Leave a comment:
-
Re: LG 42lg30-UD... no picture
I tested as posted, I forced on the inverter by jumping the 5v standby voltage trough a 1k resistor to the on/off signal of the inverter board. This powered up the inverter board and backlights ARE working.
Where would the problem be that would keep the inverter board from getting the on signal, in the power board or the main board? or something elseLeave a comment:
-
Re: LG 42lg30-UD... no picture
Thanks for the manual!
A couple questions.
on the double pin connector of the power board the 16.5v pin is only putting out 15.6v, could this be a problem?
the on/off pin on the double pin connector has 2.8v, the pwm-dim has 1.6v.
the PWM-dim pin of the inverter has 2.6v, while the on/off only has 1.4v
Are the ON/OFF and PWM-DIM pins the "same" on the double pin connector and the inverter cable connector? seems weird to me to have 2.8v at ON/OFF and 1.6v at PWM at the double pin connector, then...Last edited by stratos976; 01-19-2015, 08:05 AM.Leave a comment:
-
Re: LG 42lg30-UD... no picture
Here are connectors on power board....Leave a comment:
-
Re: LG 42lg30-UD... no picture
These are power supply pics. I checked voltage out on all the pins, I wrote down what I saw but I really don't know if they were proper or not. Nothing on the board to me looked visually bad or that it had become overheated. both fuses were good. pics are clockwise around board starting at bottom right corner where power enters....Leave a comment:
-
Re: LG 42lg30-UD... no picture
Here are pics of Inverter board front and back. I took a close up of the caps as the connections to me looked like they got hot. This board is getting
24.8v on pins 1-5,
pin 11 (VBR-A) was 1.6v,
pin 12 (on/off) 1.4v,
pin 13 (VBR-B) 2.6v,
pin 14 (errout) 0v
Can the output to the bulbs be checked?...Leave a comment:
-
Re: LG 42lg30-UD... no picture
Ok I'll work on the pics. I'm assuming the power supply board is the tan one, would the board on the far left under the metal cover be the inverter board?Leave a comment:
-
LG 42lg30-UD... no picture
I was given a LG 42g30-UD, because the picture doesn't work. With the help of this forum I was able to repair my Samsung Plasma so I thought I'd give this a shot also.
I've searched on here but need some direction to troubleshoot further, as other sets close to this model seem to be "-UA" and have more boards in the back.
when you power on the set there is [B][I]no[/I][/B] flicker or flash of backlight, just dark, but there is sound. With a flashlight, I am able to "see" snow on the screen and also the input options if I scroll though them. I've added a couple... -
-
-
-
Re: Samsung PN43D450A2DXZA, won"t come on
On my known bad boards. the three devices at the top left are all shorted 1-3,1-2,2-3. Same with the three at the centerline of board. I tested board as it sits in pic and am counting pins left to right regardless of device position (pins on top or bottom). my meter has a 6k ohm setting
Readings on uninstalled X-main.
Q4002: 1-3: 5.4k, 1-2: OL., 2-3: 4.2k
D4010: 1-3: 0, 1-2: OL., 2-3: 4.2k
Q4007: all OL.
Q4001: 1-3: 6.5k, 1-2: OL., 2-3: OL.
Q4000: 1-3: 6.5k, 1-2: 5.2k, 2-3: OL.
...Leave a comment:
-
Re: Samsung PN43D450A2DXZA, won"t come on
No flash of light, when applying power or when pressing the on switch.Leave a comment:
-
Re: Samsung PN43D450A2DXZA, won"t come on
could the logic or power board kill it?
all of the 5.3v pins on my power board show continuity to ground around 47 ohms resistance... not 0 like lead to lead or ground pin to frame show.
I'm hesitant to put this X-main in, in fear I'll fry itLeave a comment:
-
Re: Samsung PN43D450A2DXZA, won"t come on
i recieved a replacement X-main, is there a way I can double check this board (without a scope) to see if its ok before i install it.
I'm also 99% sure my new y-main and y-buffer are ok, is there anything else that could take this board out?Leave a comment:
-
Re: Samsung PN43D450A2DXZA, won"t come on
here are a few pics of the Xmain, if anyone could point out what to test on it.
Also could it be something in the TV that killed this "working" board immediately upon initial powerup? The Ymain and Ybuffer are new and as of now still appear ok....Leave a comment:
-
Re: Samsung PN43D450A2DXZA, won"t come on
Update: I ordered a y-main, y-buffer, and Xmain. Installed all three, but believe I may have a bad "new" (Refurb) xmain.
TV showed same symptoms when plugging it in, clicking and no picture, no voltage on vs/va.
I unplugged ymain from PS and would get chimes and correct voltage on vs,va
Plugged Ymain back in and unplugged Xmain, still had chimes and 207v on VS and 59v on VA. Bad Xmain or other issue?Leave a comment:
No activity results to display
Leave a comment: