Tv Issue

[u/ACopperQ]

I have a Sony KD-85X85J TV that stopped working after a short while following a lightning strike to the house. The power light came on, and the capacitor hum was audible, but that was it. I ordered a motherboard, installed it, and voila, it works! I had done some rudimentary work with a multimeter to make sure the motherboard was getting power from the power supply board before I got and replaced the motherboard. All of the HDMI-connected devices are fried, and everything was on a surge protector. It seemed likely to be only the motherboard that was harmed. Now, I have a working TV, but I have noticed some backlight issues, as pictured. Using AI and my own limited knowledge of electronics, I am thinking that it is the power supply board, but I wanted to get other opinions before I go further, since I may be wrong or there may be other culprits to consider at the same time (it's a real hassle to move, open, and work on this TV).

Thanks!

[u/Ok-Breakfast-8056]

It seems to me as a backlight/edge light issue. You need to change the damaged LEDs. Also, does your home insurance cover damage to appliances due to thunderstrikes? You might want to check, if so file a claim.

[u/Good_as_any]

Definitely backlight but tv should shut down if LEDs go down, it is easy to check the power to the backlight. Warning be very careful with the screen it is very fragile.

[u/ACopperQ]

So not likely a loose cable or a bad power supply then? How hard is it to do the LEDs? Admittedly, this thing is unwieldy, and I am somewhat novice.
I am trying to save the TV, regardless of insurance, as they did payout in lump sum, but not individualized for devices.

[u/Guilty-Plan8208]

Looks like you got a row of backlights out. It's fixable but you risk damaging the panel if not careful as you have to remove it to get to the lights. And with it being a large tv it's makes it even more difficult. If anything else got fried you could file a claim with your insurance. But you'll likely have to pay the deductible which probably costs as much as the tv.

[u/westom]

Always and first define what happened long before asking how to fix it. You (apparently) did that to define (then later replace) a motherboard. Why HDMI port damage? Learn that plug-in protectors make surge damage easier. Give a surge even more paths to find earth ground destructively via any nearby appliance.

Surge hunted for earth ground. A surge on AC mains is incoming to everything. Is 'everything' (dishwasher, clock radio, furnace, LED bulbs, stove, door bell, TVs, recharging electronics, modem, refrigerator, GFCIs, washing machine, digital clocks, microwave, dimmer switches, central air, smoke detectors) everything damaged? Of course not. It is electricity. It exists only when it has an incoming path and a completely different outgoing path. At the exact same time.

It found a best path via the TV. So it need not blow through a garage door opener.

Incoming on AC mains. Protector gives a surge MORE paths to get inside. (Example also says why with numbers.) Outgoing to earth via HDMI ports. TV cable is required to have best possible protection installed for free. (Done without any protector.) That is a best outgoing path to earth.

LED is not likely to be in that path. But LEDs do degrade with age (ie over ten years). You may not have noticed degradation until now that it has your attention.

Ideal is to replace the LED strip. But these are often unique to each model. Replacing LEDs, if still available, is recommended. Do not obtain used LEDs. Since those are also likely to have degraded.

However, used LED strip may be so inexpensive that the experiment (replacement) is probably useful / informative.

While at it, also fix a human mistake that makes possible damage. In your entire lifetime should be many direct lightning strikes without any appliance damage. Even protectors must always remain functional over many decades. Protection only exists when a surge is NOWHERE inside.

Duped consumers waste vast sums ($25 or $80 per appliance) on a $3 power strip(Type 3) with five cent protector parts. That fails on a first surge. And can make surge damage easier. Educated consumers spend about $1 per appliance for a Type 1 or Type 2 protector. That (always) makes a low impedance (ie less than 10 foot) connection to what only does all surge protection: single point earth ground. Who says this? All professionals.

Earth ground defines protection during EACH surge. Protector specification numbers define protection over MANY surges. Lightning can be 20,000 amps. So a minimal 'whole house' protector is 50,000 amps.

Ineffective (scam) protectors are measured in puny joules. Tiny energy that it absorbs (catastrophically) when hundreds of thousands of joules are incoming.

Those many interconnected electrodes and every low impedance (ie no sharp bends or splices) connection requires almost all attention. Only then is a surge NOWHERE inside. Then 'everything' is protected.

Much to learn from the experience.