Re: RCA L32WD22 No back light power on voltage from logic board.
Thanks BudM. Main board for under 30.00 and all is good.
Wingryder
Senior Member
Last Activity: 07-17-2018, 09:45 PM
Joined: 10-11-2015
Location: Cedar City, Utah
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Re: RCA L32WD22 No back light power on voltage from logic board.
Thank you for jumping in BudM. I will get one coming and see if all is good.
dmLeave a comment:
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RCA L32WD22 No back light power on voltage from logic board.
32 Inch LCD Amber Standby light.. goes green with power, times out after 30 sec. and flashes. No screen, no audio. 24, 15, 12 and 5 voltages are there on the supply. (however one thing..they are all there during standby. Thought that was strange.) Caps look good. Nothing wrong with supply.
Further testing showed no BL voltage, should be over 3 volts according to BudM.
Digging deeper and what a pain this backwards built tv is to work on, I find serious damage on the tuner/logic/main (I never know what to call this one)
Looks like someone plugged or unplugged a hdmi... -
Re: Substitute CCFL backlights in Sanyo
Thanks for the input.. Well good news its lives. Removed the LCD panel so I could see the lights and the short one was working fine but there was one more out that did not look burnt. Put another donor lamp in that slot and she stays on and looks great.
I was a little worried about those ribbons tabs on the lcd panel because of all the teardowns... but they survived and picture looks good. No lines or troubles.
Will let it play all afternoon and I will get it back to the friend that gave it to me.Leave a comment:
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Re: Substitute CCFL backlights in Sanyo
Well no joy. I put it back together and still have the same two seconds and then the backlights go out. I did not know how to leave it partial apart so I can see what is happening. Don't think the donor lamp is working.
So what happens if you leave the lcd screen out.. tcon board unplugged etc.
will the safety circuits stop the backlights from even trying to light?
Feel free to jump in... Is it because the lamp size is wrong??? There might be more than one out.... The one I replaced was black all the...Leave a comment:
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Re: Substitute CCFL backlights in Sanyo
Looking closer my donor lamps are maybe one size larger than the originals. The ends still fit the clips so it's not much. Will this cause any grief with current draw?Last edited by Wingryder; 01-22-2016, 06:08 PM.Leave a comment:
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Substitute CCFL backlights in Sanyo
I have A Sanyo 42 Inch with one backlight ccfl burned out. This is causing the one second to black that is discussed in length on this forum.
I have some ccfls from a different tv set that are the same size diameter wise . But are about 5 inches shorter.
I want to clip one end of my shorter tube in as normal and then support the other end with a plastic support so it is not just hanging in the air.
And then run a wire from the end of the ccfl to the other clip. ?? Will this work?
I am not worried about loss of light. Just want the TV to... -
Re: Element 50 in (I think ELEFT502) no backlight
Well got frustrated and sold this one locally non working. Sellers remorse a bit but the Element bad reputation worried me. On to the next.Leave a comment:
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Re: Element 50 in (I think ELEFT502) no backlight
Thanks lookimback No bench supply here but I did measure across each of the five connectors as I powered up. #1 had 3.5 volts for a second, #2 comes up to 3.9 volts and stays there.... and the rest have no voltage. (this is with all still plugged in of course)
So Power supply or Bad Panel ? or too early to tell?Last edited by Wingryder; 01-18-2016, 09:51 AM.Leave a comment:
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Element 50 in (I think ELEFT502) no backlight
P.O. says sound worked and no picture. For me Red light turns blue and it stays on. . No sound or picture. With flashlight I can see the menu come up very dim.
Nothing jumps out with back off except how little is in there.
Power supply
Tcon board and tuner board.. That's it. I get 167 volts on standby and 390 with set on across the large filter cap on hot side of supply. From other posts these are normal. On Connectors 1 through 5 I have a red and white wire each going into the panel on the left side. I assume these are feeding the led backlights. Do I test the output with...Last edited by Wingryder; 01-17-2016, 11:42 AM. -
Re: LG 47LH90 No standby voltage
Correction I plugged in main board to make it easier to probe connector for 5 volts. That's when I got the standby light for the first time. Now just got to find the broken trace or bad joint. Still pretty stoked.Leave a comment:
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Re: LG 47LH90 No standby voltage
Bud you are not going to believe this. Put the board back in to take those measurements.. checked them a time or two and looked down and had red standby light. Could not believe it. Shut everything down again and waited a few minutes then hooked main board and inverter board back in. Plugged in in.. standby light was on. Power it up and looks great. Audio is there and picture full of snow which delighted me. (no input yet). Family calls so that's it for tonight at least. Must have a bad joint on that board. It might be hard to find. So far those...Leave a comment:
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Re: LG 47LH90 No standby voltage
Ok some big changes. I would swear I was getting that 46 volts at the fuse with the power switch turned off. I thought this circuit was active just when plugged in. (standby)
Anyway now it is about 3 volts with the switch off and I guess goes to nothing if the caps are fully discharged.
Power switch on and 166 volts on the fuse.. and on the Fuseable resistor R501. I now get about 14 volts across C506.. Still nothing from drain to ground on IC in question.Last edited by Wingryder; 12-23-2015, 07:29 PM.Leave a comment:
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Re: LG 47LH90 No standby voltage
Bud
I see no voltage on 506Last edited by Wingryder; 12-23-2015, 04:06 PM.Leave a comment:
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Re: LG 47LH90 No standby voltage
Bud Sorry about the misleading you with the 380 volt comment. I do not have this. I only have the 166 out of the Bridge for standby. Then it drops to 46 at the Fuse.. After that I did not know where to test.
To answer your question about the cold side rectifiers. The Scottky's on the heatsink measure .171 and .343 for the en220a's and the en210a was .171/.425 (both sides)
This was in circuit ... but where they were all pretty much the same I think they are ok.
Here are some more pictures.. hope they will work
...Last edited by Wingryder; 12-23-2015, 11:12 AM.Leave a comment:
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Re: LG 47LH90 No standby voltage
Bud I do not get the 360 volts mentioned... I was just explaining how it should work.
I get only the 160 standby . Better Pic tomorrowLast edited by Wingryder; 12-22-2015, 06:08 PM.Leave a comment:
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Re: LG 47LH90 No standby voltage
R501 2.3 ohms
ZD502 30.k one way and ol the other
D201 seems to climb up to around 1k measuring from middle leg to both sides and about the same reversing leads. I will take it out and recheck it in the morning.. ran out of time today.
Big thanks for your timely help.Leave a comment:
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Re: LG 47LH90 No standby voltage
Quote "Did you also already test the rectifier diodes in the cold side of the STBY power supply? there is a Zener right under that IC that looked open until I took it out, then tested ok. I have tested most small diodes and nothing jumped out at me.Leave a comment:
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Re: LG 47LH90 No standby voltage
Here are the requested pic. No sun today so.......Leave a comment:
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Re: LG 47LH90 No standby voltage
Bud
It is XK942015x04
ICE 3B0365J
G0930L0P
Hard to read hope it's correct. Working on the requested pictures.Leave a comment:
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