25" K7191 White Screen

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Working on a machine for a client, I already told him he needed a new power supply and he bought it and had some other dude go in and fix it. (Same dude that cut half the wires that I had to fix because he has no clue what he's doing... but that's a different story)

Anyways now that the boards are up and running and you can hear the sounds all he gets is a white blank screen with NO feint image or anything "behind" it, same as if when the boards were not getting power. Thoughts?

He refuses to let me take the chassis home and it's like a 40 minute trip that I'm not really getting paid for, so the less trips to "check" things the better. Kind of just looking forward to closing up this deal.
 

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Is it rolling?

There's something like it on the video but I'm pretty sure that's just video being video, the guy described it as "a little wavy" but not sure what he means by that. When I saw it in person it wasn't rolling and just had the white screen. (With bad caps causing some issues on the edges, but that's that)
 
if it's a full bright screen with retrace lines it'll be the G2 wire not making connection somehow. at least that's what I've seen. someone did a hacky solder job on the pin. I may have either reflowed the pin properly or hardwired the G2 wire in place of the pin. don't remember off-hand. either way, that fixed the problem. THEN I capped and reflowed the rest of the chassis.
 
if it has not had a cap kit at minimum, that has to be done first.

the grey screen is also cause by a bridged solder joint in the video circuit and it can also be from a broken trace or pad.

i have see all of this cause issues like yours.

dude needs to either let you repair it or stop wasting your time and send it out.

Peace
Buffett
 
The good news is the majority of the monitor boards stages are running.
could be all too and you are just lacking a good input game signal.

So adjusting the bottom knob of the flyback doesnt back down on the white splash screen?
If i remember correctly a g2 open is normally results in a no image at all. some will go white splash if the g2 is open depending how the monitor board drives the guns.

video signal processing is not real common in a k7000 but if you are absolutely sure you have a good signal feed and its in the monitor board than maybe a blow upc1397 however a fairly rare fail. probably terminal, wiring connection mishap though from the sounds of it with your mentioning cobbling of wires.

and yes, you really need it on a bench at home where you can work on it properly. I would never want to work on something inside a cabinet. its not like we are mobile clinics!.
 
Had one that was doing the exact same thing. White raster with no video. Check all the voltages on the pins of IC 1. I found on the one I was working on pin 9 had no voltage. The problem was the jumper on the board from pin 9 to R16 was not soldered in the board very good (cold solder joint). Put a new jumper in and now have video with a great picture.

Hope this helps.

If you need a second set of eyes to check it out let me know.

Ed
 
Thanks guys. Gave him the ultimatum that I need to take it home and work on it on my bench and I'll charge a flat rate + parts, or I'm going to pass on this job. The drive is like 25-30 minutes and I haven't even been charging him for that.

The other tech was positive it was trash because it had a wire jumper on the bottom of the PCB. Ugh. What a shitshow repair can be sometimes. :p

Luckily I think I have the same monitor in my spares, so at least I have something I can test on when I bring it home. Probably will just go in and reflow solder and put in new caps to start or see if there's anything I can see with the eye that might be the issue. Of course checking out what purpose that wire jumper is doing would be the first thing as well.
 
Great, I'm getting paid fairly for this cap kit and we had a misunderstanding for bringing it home, he thought I meant the whole monitor, so I get to bring the chassis to my nice bench in New Jersey and figure out what is up.

I wonder what a fair price would be for this minus parts. (labor-wise)

Thanks again guys. Will inspect closer once I get it in my hands.
 
Any updates? THIS IS HAPPENING TO ME! I've already replaced most of the easy parts. Just need a little bit more guidance.
 
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