Need T-Con Advice (Vizio P602ui-B3)

[Jidis]

Hi all,

I made a big-ass mess here of my father's beloved P602, and I'm trying to figure out if I should order a batch of overpriced ribbons or if I'd just be throwing more good money at the bad.

He woke up recently to a bunch of white bars going down the right side of the screen. From what I'd seen in these places, I figured the T-con board has gone out or has a bad connection. I took the back off and gently poked at the socketed ribbons and sure enough, got the image back. It was mainly the far left ribbon, and it would snap back to stripes if I let off the pressure. I figured, "Great... I can just reflow the connector and clean things.". I wiped it with some flux and hit it with hot air (actual rework station), but was probably too much of a wimp on the heat, so it looked great for an hour while I tested it, then ten minutes after he sat down it snapped back to lines. He keeps the volume jacked up to something ridiculous, so maybe it needed a little shake.

Being fairly confident now that it was likely just open joints and I could maybe get by without ordering a board, I went back in with a vengeance and screwed up a bunch of stuff in a hurry to get it back up and running. I fluxed again, but this time, went across the pins with a chisel tip iron and a bit of fresh solder, which spread all over everything (as expected). I figured to soak up most of it with braid and clean the ribbons more thoroughly. Long story short, my Opti-Visor magnification wasn't up to the task, and I was too sloppy, and didn't spend enough time checking my work. It powered up to a backlit black screen and gently touching the ribbons did zilch. Turns out, not only had the braid left a bunch of pins bridged that I could have easily seen, but the edge lines on two of the ribbons had lifted from the substrate and were all crossed up and smashed (probably from the alcohol & brush). I figured I'd powered up with a bunch of shorts, and may have killed the T-con, so I went ahead and ordered a replacement for $25+10. The ribbons were looking really difficult to repair, so against most advice I saw online, I attempted to slice off about a millimeter of the end of the two bad ones and check them thoroughly with a USB microscope. I also had to slice the little index tabs from the sides and take extra caution to see that they went in straight.

As I'm now in here, you may have guessed that it still didn't work. The images show about what it did with different combinations of ribbons connected if that can tell you anything, but my main question would be, is the circuitry on the panel resilient enough to live through such a catastrophe, and should I go ahead and order clean ribbons, or is there good chance I zapped something on that first run and will just get the same result? FWIW, in the images of P602 ribbons I saw, they appear to have the same contacts at each end, so they evidently are the type that can detach, but I have no idea where they go once they disappear into the frame or how much trouble it is to get to their sockets.

Much appreciated and sorry for the long text,

George

[nomoresonys]

It's a pretty good tv, currently have same one in the living room. If the ribbon cables are messed up you will need replacements. The problem may have been that the ribbon cable ends just needed cleaning, a pencil eraser works good for that. If you messed up the tcon connector it's probably just easier to get a replacement tcon, they usually aren't too expensive at all. Need to make sure you match the numbers on the stickers of the tcons to insure a match. If it was me I'd give it a try.

[Jidis]

nomoresonys - Yeah, all that stuff was done already. Replacing ribbons is an option I guess, but they're as much as the T-con board cost me, and I was hoping maybe someone could tell from the pictures or description if that sounded like a lost cause. It definitely was a winner back in its day. I got it per recommendations (either here or AVS), and he has run it all day, every day since it was new. I replaced three or four supply caps once, but that was it, and it would still be running now if I hadn't ruined it.

Wish there was a cheaper source for those ribbons. The overpriced ones I found weren't even 100% new.

Thanks!

[nomoresonys]

Well I've already cut off just the very ends of a frc cable to make it work, should be fine as long as it's even and each only contacts the line it's suppose to. You can check the continuity with a multimeter, just put a probe on each end, if they all show good then the cable should be fine. So you just cut off a fraction if you cut off too much then you won't have the contact of course.

[nomoresonys]

Check youtube, there's quite a few videos of people fixing them with basic tools, mostly just a sharp edge utility knife. I think I just used scissors.

[Jidis]

Thanks again nomoresonys - The cutting's already happened too. The second picture is the contacts on one of them afterward. If they look random or uneven, it's actually because I read that you need a tool with a "guillotine" type action, rather than scissors or knives that cut across the pins, as that can spread the copper sideways. I tried to do the chop-down way with a really sharp new scraper blade, but the ribbon was too tough, so I ended up using the blade as an edge and running a really sharp razor knife across them. I propped the ribbon up on something afterward and gently filed downward in the direction of the wires at an angle with a diamond file to get rid of any smeared strands or anything from the side-to-side cutting.

The pitch of this thing is ridiculous. If I even try to clean it up with a really small blade, the whole area is obscured by the tip of the tool, so I figured looking at it with a microscope would have to suffice (rather than continuity checks). I'm actually sort of worried that there isn't anything wrong with my ribbon trimming, as that would mean that there's nothing left I can swap to fix it.

Take Care

[nomoresonys]

Well you gave it a hellofa effort, might be time to pack it in.