Insignia NS-55E480A13A. Backlogs flicker, then black screen.

[sameoldsam]

Re: Insignia NS-55E480A13A. Backlogs flicker, then black screen.

ok, I think I located them. They are white, rectangle/oblong with gold on ends. Very small. Actually 2 are small, is very, very small. There is a F6.3A/125V near the 2 small ones, and near the even smaller one is F1A/63V. If those are indeed them, how do I test them?

[budm]

Re: Insignia NS-55E480A13A. Backlogs flicker, then black screen.

Insignia/Hitachi/Philips/NEC 55.55T02.D01 LED Driver
Provided by shopjimmy.
LCD panel has 8 LEDs strings.
The LED driver board has two boosconverter circuits, one per set of 4 LED strings.
There are 8 PWM Controlled MOSFETs (Q44 ~ Q50) for 8 LED strings.
There are 8 Cathode return pins on the LED connector:
VFB1-1 ~ VFB1-4 (PIN 3, 4, 5, 6)
VFB2-4 ~ VFB2-1 (PIN 7, 8, 9, 10)

1) You will need test the DC V you have on V boost1 and V Boost 2 EVERY TIME you turn on the TV.
2) You will need to test the DC V on all 8 pins of the Cathode return pins 3 ~10 EVERY TIME you tun on the TV.
Basically you will be turning TV on and off many times to check all the Voltages on those pins to find out which LED string is bad or which boost converter is bad, that is what I will do.
BTW, you will see the Voltages change very fast so you must keep the probes connected and keep your eyes on the meter every time you turn on the TV otherwise you will miss the readings.

[budm]

Re: Insignia NS-55E480A13A. Backlogs flicker, then black screen.

ok, I think I located them. They are white, rectangle/oblong with gold on ends. Very small. Actually 2 are small, is very, very small. There is a F6.3A/125V near the 2 small ones, and near the even smaller one is F1A/63V. If those are indeed them, how do I test them?

Check the resistance between the two ends of the fuse, meter set to 20 Ohms scale (unless your meter has 2 Ohms scale), the reading should be same when you touch the two probes of the meter together.

[sameoldsam]

Re: Insignia NS-55E480A13A. Backlogs flicker, then black screen.

Ok, fuses are good. Your next post...Wow. I've located everything on the board. I think what you are telling me is... Turn on TV and test VB1(which are pins 1&2) and VB2 which are pins 11, 12. Then test first pin(pin 3). Turn tv off. Turn on TV and test VB1 and VB2 again, then test next pin(Pin 4). And so forth down the line. I know how to test the pins, but do I test VB1 pins 1&2 differently? together or separately? What kind of numbers am I looking for? Thank you again!!!!

Edit: So I see pin 1 and pin 14 have a wire, pin 2 and 13 do not, so just test the pins 1 and 14 as I would other pins.

[budm]

Re: Insignia NS-55E480A13A. Backlogs flicker, then black screen.

Just test right at the pins that are soldered to the board.
Pin 1 and pin 2 are tied together on the board so it does not matter if you put the red probe on pin 1 or pin 2, same for pin 13 and 14, they are tied together.
So you will keep black probe attached to the chassis, the keep the red probe on either pin 1 or pin 2 then turn the TV on while keeping and eye on the meter, you will need to leave the meter on 200VDC scale because the Voltage should jump up over 100V when you first turn the TV.
I believe what you will see on the Voltage on the meter will jump up over 100V when you see the backlights flash on then after about 5 seconds or so the Voltage will drop down to 24VDC due to protection circuit kicks in.
You will do the same on other pins.

[sameoldsam]

Re: Insignia NS-55E480A13A. Backlogs flicker, then black screen.

Ok, thank you so much! I love learning all this! I will be able to test later in AM. I'll let you know the readings when I can.

[budm]

Re: Insignia NS-55E480A13A. Backlogs flicker, then black screen.

"same for pin 13 and 14, they are tied together" my error.
BTW, pin 12 and 12 are tied together for V boost 2, connector only has 12 pins.

[sameoldsam]

Re: Insignia NS-55E480A13A. Backlogs flicker, then black screen.

Hi!

I tested:
VB1-
Pin 1. 00 - TV ON went to 23.4 on startup. Spiked to 108 when backlights flashed, then back to 23.4
VB2-
Pin 12. 00 - TV ON went to 23.4 on startup. Spiked to 90 when backlights flashed, then back to 23.4

VB1
Pin 3. 00 until Backlights flashed, spiked up to 28 then back to 00
Pin 4. 00 to 28 to 00 same
Pin 5. 00 to 27.5 to 00
Pin 6. 00 to 25.8 to 00

VB2
Pin 7. 00 to 14.4 to 00
Pin 8. 00 to 15.1 to 00
Pin 9. 00 to 4.5 to 00
Pin 10. 00 to 2.5 to 00

Pictures show how I did it for Pin 1 and Pin 12(although photo says Pin 14). Each tested individually while tv was turned on.

Hope I did this right! But I have a feeling I should have done more. This is a start though, I hope.

[budm]

Re: Insignia NS-55E480A13A. Backlogs flicker, then black screen.

Hi!

I tested:
VB1-
Pin 1. 00 - TV ON went to 23.4 on startup. Spiked to 108 when backlights flashed, then back to 23.4
VB2-
Pin 12. 00 - TV ON went to 23.4 on startup. Spiked to 90 when backlights flashed, then back to 23.4

VB1
Pin 3. 00 until Backlights flashed, spiked up to 28 then back to 00
Pin 4. 00 to 28 to 00 same
Pin 5. 00 to 27.5 to 00
Pin 6. 00 to 25.8 to 00

VB2
Pin 7. 00 to 14.4 to 00
Pin 8. 00 to 15.1 to 00
Pin 9. 00 to 4.5 to 00
Pin 10. 00 to 2.5 to 00

Pictures show how I did it for Pin 1 and Pin 12(although photo says Pin 14). Each tested individually while tv was turned on.

Hope I did this right! But I have a feeling I should have done more. This is a start though, I hope.

It looks like you have problem with those two LED strings.

[sameoldsam]

Re: Insignia NS-55E480A13A. Backlogs flicker, then black screen.

I found a couple videos on replacing the LED strings for different tvs. Can't find LED strings for this TV though. I'll keep looking. I also saw videos of replacing just the single leds but haven't watched those yet. I sure hope it can be done for this TV. Thanks budm, I've learned so much from you and everyone on this thread!

[budm]

Re: Insignia NS-55E480A13A. Backlogs flicker, then black screen.

Look for at the back of the LCD panel to get the model number since LED assemblies have to be matched with the panel.
See if your panel is AUOPTO T550HVN01.1

Edge lit LEDs for the above panel:
http://www.shopjimmy.com/hitachi-phi...s-2-strips.htm

[nomoresonys]

Re: Insignia NS-55E480A13A. Backlogs flicker, then black screen.

https://www.youtube.com/watch?v=YgaL6X6eSaU

[sameoldsam]

Re: Insignia NS-55E480A13A. Backlogs flicker, then black screen.

AUOPTO T550HVN01.1. Yes. Not in stock but i will search.
Going to watch video now.
Thanks guys!!

[sameoldsam]

Re: Insignia NS-55E480A13A. Backlogs flicker, then black screen.

Can't find anywhere. IS single replacement of bad LED's out of the question or is it the same problem with locating the correct ones?

[diif]

Re: Insignia NS-55E480A13A. Backlogs flicker, then black screen.

Can't find anywhere. IS single replacement of bad LED's out of the question or is it the same problem with locating the correct ones?

I only ever replace the failed LEDs, they are cheaper and easier to source than whole strips and whole strips tend to be second hand anyway.

[nomoresonys]

Re: Insignia NS-55E480A13A. Backlogs flicker, then black screen.

http://www.shopjimmy.com/catalog/pro...rework-station
There's some there BUT not sure if they match, shopjimmy does sell them, maybe call them and tell them your model and panel number, maybe they can match you up, "T550HVN01.1" yes I think you have the right number there.

[sameoldsam]

Re: Insignia NS-55E480A13A. Backlogs flicker, then black screen.

I only ever replace the failed LEDs, they are cheaper and easier to source than whole strips and whole strips tend to be second hand anyway.

How would I find out what type of individual LED's I would need? Thanks

[sameoldsam]

Re: Insignia NS-55E480A13A. Backlogs flicker, then black screen.

http://www.shopjimmy.com/catalog/pro...rework-station
There's some there BUT not sure if they match, shopjimmy does sell them, maybe call them and tell them your model and panel number, maybe they can match you up, "T550HVN01.1" yes I think you have the right number there.

Thanks, they are out of the strips, but your link has the individuals. Hopefully I'll have time tomorrow and I think I will give them a call and see what they say about it...and me trying to do it...LOL

[sameoldsam]

Re: Insignia NS-55E480A13A. Backlogs flicker, then black screen.

Look for at the back of the LCD panel to get the model number since LED assemblies have to be matched with the panel.
See if your panel is AUOPTO T550HVN01.1

Edge lit LEDs for the above panel:
http://www.shopjimmy.com/hitachi-phi...s-2-strips.htm

They are out of stock and indicates likelihood of getting them is slim. I did put my name on the email list just in case though. Thank you.

[diif]

Re: Insignia NS-55E480A13A. Backlogs flicker, then black screen.

How would I find out what type of individual LED's I would need? Thanks

You can disassemble the TV to get to the LED strip, then measure the LED and order locally, ebay or from China, Aliexpress.

Or buy one one of these and hope it's got the one you need https://www.aliexpress.com/item/1W-0...814758317.html

I've got one and although not always the same colour it has most of the common sizes and both of the voltages.