Re: Samsung QLED QN55Q80RAFXZA - No backlights
tvpartstoday dispatched the replacement parts immediately after I submitted the form on their website. I had 5 days to determine if the replacements worked and then they would tell me the next step regarding returning the bad parts. They shipped them fast and I received them in 2 days. After I let them know it was successful they instructed me to just recycle the parts myself… no need to send them back.
On the whole, I am satisfied with my experience with them. Sure I would have liked to get working parts the first...
DennisKal
Member
Last Activity: 01-14-2023, 04:49 PM
Joined: 01-05-2023
Location: Manassas, VA
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Re: Samsung QLED QN55Q80RAFXZA - No backlights
I received a replacement power board from TVPartsToday and very pleased that the TV immediately worked. I really appreciate the insight and help on the debug of what was happening. You guys found the issue quickly which enabled me to request the replacement.
Next time I’ll start here!Leave a comment:
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Re: Samsung QLED QN55Q80RAFXZA - No backlights
Davi.p,
Since I have easy access to the back side of original dead power board, I checked the trace for B13V. You are right that it goes to the center leg of QM884. I double checked again the new board that we have been debugging on the top side and it shows no connection. I don't want to peel up the glue on the bottom side sine I plan to return it as defective to hopefully get another board that works.
Will post an update after that.Leave a comment:
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Re: Samsung QLED QN55Q80RAFXZA - No backlights
Davi.p, I checked it from the top side with a digital voltmeter. All three pins were accessible. None showed connectivity to B13VLeave a comment:
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Re: Samsung QLED QN55Q80RAFXZA - No backlights
Davi.p, I don't think B13V is connected to QM884. The bottom leg is A13V but neither the top leg or middle leg is connected to B13V.Leave a comment:
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Re: Samsung QLED QN55Q80RAFXZA - No backlights
Davi.p,
CNM801
Pin 5: VAMP = 18.1V
Pin 7: VAMP = 18.1V
Pin 11: A13V = 13.04V
Pin 13: A13V = 13.04V
Pin 13: A13V = 13.04V
Pin 17: A13V = 13.04V
Pin 16: Power On/Off = 3.3VLeave a comment:
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Re: Samsung QLED QN55Q80RAFXZA - No backlights
Storyteller12, Davi.p, for a test what would you think of jumpering the failed fuse on the original power board to see what we see? Maybe that is all that is wrong with that original board.Leave a comment:
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Re: Samsung QLED QN55Q80RAFXZA - No backlights
Storyteller12, with the power board powered up, but the Main and LED Driver board connectors disconnected, Pin 13 measured 4.9mV.Leave a comment:
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Re: Samsung QLED QN55Q80RAFXZA - No backlights
Davi.p, here is the picture of the back side of the power board. Not much sunshine here today so let me know if I need to take another with better lighting....Leave a comment:
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Re: Samsung QLED QN55Q80RAFXZA - No backlights
Storyteller12, also on the old board, the fuse next to the power cord connecter, FP801S, is blown. This was surely the original problem but I suspect it had other effects downstream.
When I installed the boards, I didn't make progress until I changed both the Power and Main boards. I tried them one at a time in different order and did not get to where the unit powered on at all.Leave a comment:
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Re: Samsung QLED QN55Q80RAFXZA - No backlights
Storyteller12, with the old power board, Pin 13: B13V = 0V. All zero's on the other pins as well.Leave a comment:
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Re: Samsung QLED QN55Q80RAFXZA - No backlights
Thanks Davi.p.
When all connectors in place:
CNV901A 6.Fault = 0.69V
CN9001A 5.Blu On/off = 2.95V
With power connector to Main board removed:
CNV901A 6.Fault = 0V
CN9001A 5.Blu On/off = 0VLeave a comment:
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Re: Samsung QLED QN55Q80RAFXZA - No backlights
Pictures of the three boards in question...Leave a comment:
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Re: Samsung QLED QN55Q80RAFXZA - No backlights
I took these measurements on the Power board connector that leads to the LED board on the pins that were accessible.
All connectors in place. Powered up.
- 18-pin connector on Power Board: measured between Pin X and Pin 17
- Pin 1: GND = 0V
- Pin 3: VDRV = 33.36V
- Pin 5: VDRV = 33.36V
- Pin 7: VDRV = 33.36V
- Pin 9: VDRV = 33.36V
- Pin 11: GND = 0V
- Pin 13: B13V = 2.6 mV
- Pin 15: FB = 0.39V
- Pin 17: GND
Removed...Leave a comment:
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Re: Samsung QLED QN55Q80RAFXZA - No backlights
I do have a multimeter. Can you advise on where to test for power and what values I am looking for?
Also, the part numbers I installed are
- Main: BN94-14058G
- Power Supply: BN44-00987A
- LED Driver: BN44-00985ALeave a comment:
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Samsung QN55Q80RAFXZA - No Backlights
I posted the same message twice. I apologize for the error. -
Samsung QLED QN55Q80RAFXZA - No backlights
Hi, I am working on a 2020 Samsung QLED QN55Q80RAFXZA Version FA02. On Christmas Day, the TV made an odd sound while off (in standby). After that it would not turn on. There was no red standby light.
Based on what I read on the net, I ordered and replaced the Power Board, the Main Board and the LED Driver board with a kit from TVPartsToday. After these were installed, the TV would start up and play the startup tone but the screen was still dark. By shining a flashlight onto the screen, I could see the faint image that was on the screen as it was in the startup mode looking for... -
Re: New Members - please post your introductions here
Hi everyone. I'm Dennis from Virginia. Looking forward to finishing a repair on a Samsung QLED TV.Leave a comment:
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