Black screen on Sony 65x90ch (65x900h from Costco)

[nomoresonys]

Go ahead and check F 1000 and F 1001 on the green LDA board, make sure they have continuity.

[Adam Russ]

Seems like the connector wouldn't even go back on easily, with a jumper left in.

No, this was a rigged up jumper done with very thin wires. The wire mainly popped into thr very small space between the plastic clip and wire harness itself. Didn't use resistors either as I guess I should have. Hopefully I'll come across this other board.

[nomoresonys]

Seems like the connector wouldn't even go back on easily, with a jumper left in.

[Adam Russ]

Here's the thing, not sure how you did that first test with the jumpers but IF you had the cable from powerboard to motherboard UNPLUGGED as would be correct way, then you could not have damaged the mainboard at all, so were the boards connected during that jumper testing?

Main board power cable was disconnected. When I plugged the cable back in after pulling the jumper pins I'm wondering if I had only pulled 3 out fully and thr the power on one was still halfway in (it's on the bottom of the cable connector). That'd be my best guess. It might have overvolted the main. From what I've read when the main doesn't turn on its often the emmc chip

[nomoresonys]

Here's the thing, not sure how you did that first test with the jumpers but IF you had the cable from powerboard to motherboard UNPLUGGED as would be correct way, then you could not have damaged the mainboard at all, so were the boards connected during that jumper testing?

[Adam Russ]

Nope. nothing anymore. Pretty sure the main board is a goner now. I must not have unplugged the bottom jumper to the power on when I hooked it back up. measurements around the emmc were lower than what I would have expected. so my first step now is to replace the main board before I can determine if anything additional is needed. I'm actually looking for the main board that went to the spare power supply. My records dont showing being sold but I can't find it now. 😕 Thanks to everyone for their help

I may just jump over to another tv i had sitting around for awhile and try to finally fix that. it's turns on and goes to the sony logo then turns off. Guessing that'll be a bad main board too

[nomoresonys]

Ok, so from what I gather the optical no longer is lit, does the indicator led on front of the tv light up at all when you try to turn the tv on or in standby?

[Adam Russ]

Maybe youre getting terms mixed up, nowhere does it say you did a firmware update.

yeah I thought you were referring to the red light on the optical port, not the update. sorry

[nomoresonys]

Maybe youre getting terms mixed up, nowhere does it say you did a firmware update.

[EazyBone]

This is what I said to do. Jumper ps on, TCON on and stby. With main board disconnected. The 12v is what we needed. This was trying to get to the fact that the main board was effectively bad. Which is what I learned towards in the very beginning. Not sure how this wasn't communicated properly

[Adam Russ]

I decided to test if the power supply was bad, which I doubted it was. I unplugged power to tcon and main board and then jumped tcon on to standby and power on and got proper 12.7v on the tcon 12v lines. Main board is what's keeping it from powering on now. Somehow I managed to kill it after the jumper yesterday. I guess I need a new main and going back to the original issue maybe a tcon board as well. Are there any good ways to determine if the tcon is good without a working main board?

[Adam Russ]

So I'm not mistaken, I shouldn't any voltages on the tcon pins of the power board until the tv is turned on correct? They are all zero or one is -.0004

[Adam Russ]

Ok, this info. needs to be relayed early, it saves going down roads already driven and lets everyone get to solution much faster. Do you have the red optic light back on the mainboard?

I did list that before. Before I did the jumper yes. And the tv turned on. After the jumper, no. And it doesn't turn on either. But I have the 12v and 3.3/3.4 standby and power on voltage on both power supplies. My guess is the main board was affected after hooking things back up after the jumper somehow. It was working fine. Now it's totally dead. I'm likely going to have tonofmrder a new main board before I'll be able to do much else.

[nomoresonys]

I need quicker responses, my ads won't allow me to stay on one subject without input.

[nomoresonys]

Ok, this info. needs to be relayed early, it saves going down roads already driven and lets everyone get to solution much faster. Do you have the red optic light back on the mainboard?

[Adam Russ]

A simple firmware update has been known to fix this issue but who knows what is messed up now, like I said, things need to be done in order and tests need to be done correctly.

I've downloaded and installed the firmware by usb multiple times. Was one of the first attempts made before even opening the tv. Didn't fix it unfortunately.

[Adam Russ]

So what is different after jumping, ie with everything hooked up normally? did you say you had the red light at optical before jumping?

After jumping, nothing turns on. No lights, nothing. Before it would turn on and you could get audio and and have the red optical light and the backlights would be lit. After it's totally dead. No signs of life. Seeing as I have the 12v on the powerboard as well and standby and power on voltages, I'm guessing something happened to the main board when hooking things back up.

[nomoresonys]

A simple firmware update has been known to fix this issue but who knows what is messed up now, like I said, things need to be done in order and tests need to be done correctly.

[nomoresonys]

So what is different after jumping, ie with everything hooked up normally? did you say you had the red light at optical before jumping?

[nomoresonys]

BEST practice is to use about 1k ohm resistors for jumping for safety so nothing effs up during jumping. Testing should be done in order according to fault, if you can't get the tv to do what it did before jumping then you probably did mess something up on powerboard.