Toshiba 50HP66 - never turns on, clicks off when relay does

**mmartell** · 02-11-2015, 01:49 AM

Re: Toshiba 50HP66 - never turns on, clicks off when relay does

If the screen looked anything like this then you likely have a shorted fet(s) in upper and/or lower buffer board. If so do the test in my previous post.

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**vince_o** · 02-11-2015, 06:55 PM

Re: Toshiba 50HP66 - never turns on, clicks off when relay does

This is getting silly. Since the TV is laying facedown, I propped it up to see what the screen was doing. I powered it on, and instead of the vertical bars I saw yesterday, I saw an initialization message, snow, and black smears. I turned it off and then on again and the smears started going away. (It's in an unheated/chilly work area so I guess it needed to warm up a bit.)

I plugged in a Roku, changed to the proper input, and I saw the entire screen (the smears eventually went away). The resolution is a bit low but the Roku is only SD (it's first generation). I don't have easy access to anything higher quality just yet but, since it's actually coming on, I'll let it be for a couple days.

If it produces an image, does it have a faulty board still or is this just a temporary resuscitation? I thought/read that, once you heard a pop and the screen went black, that was it until a board was repaired/replaced. Should I reassemble it and mount on my wall or will that jinx it?

Thanks for any suggestions.

**mmartell** · 02-11-2015, 11:41 PM

Re: Toshiba 50HP66 - never turns on, clicks off when relay does

Black smears ? Give a feel to the two large heatsinks on the zsus, I bet one of them is cold - meaning you popped an IPM.

**vince_o** · 02-13-2015, 09:41 AM

Re: Toshiba 50HP66 - never turns on, clicks off when relay does

I also should point out that, before I made the TV vertical, screws from the y-sus and both upper/lower boards had been removed. I had removed the y-sus board (to check the underside) and had put it back in loosely because, if it was bad, I was going to take it out again.

When the screen had vertical bars, I had the grounding strap anchored and maybe one corner of the y-sus but the other screws were out. When I saw a working screen (snow at first, then Roku), it was only after I installed all screws. I don't know if that matters but it may.

I'll let it run for a while tonight and check the heatsinks to see if any are noticeably cooler than the others.

**vince_o** · 02-13-2015, 07:55 PM

Re: Toshiba 50HP66 - never turns on, clicks off when relay does

After about two hours of usage, I may have two IPMs out--lower y-sus and upper z-sus. The other heat sinks were too warm to hold long but these two were only warm.

I've attached some photos of the screen if that helps. (I reset the picture quality with the OSD menu before I started.) The input is an OTA signal which looks fine on a plain 27" CRT. The resolution on this is dismal and color changes are sluggish. If the background changes from black to blue, it takes time for the black to go away.

Thanks.

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