Home Theater Forum and Systems banner

1 - 19 of 19 Posts

·
Registered
Joined
·
14 Posts
Discussion Starter #1
Hello all, I recently picked up my 3rd Hitachi p50s601 50" plasma with the common cap and SDR board issue. I replaced the caps and fixed the SDR/buffer chip. I had an image but the tv would shut down after about 5 seconds and sit in standby mode.

I decided to take one of my working 601's and start swapping circuit boards....starting with the power supply. I ended up with all the working boards in the new/used tv and it still wouldn't work. It was turning on then shutting off.:rant:

I finally gave up and put the respected boards back into their tv's and now I have BOTH tv's doing the 4 blink!!
I am completely lost and frustrated at this point.

After going the easy route with the board swapping, I found the service manual for the tv and now will go the sensible route and start checking voltages...praying right now that I find something simple is wrong...yeah right!!!

Any feedback would be helpful, of course!

Thank you in advance!!
 

·
Registered
Joined
·
60 Posts
I assume you must be very technically proficient, as working on a power supply is very dangerous or so I read when experiencing problems with my old Panny plasma.

My vote: Buy a new TV & be done with it...I did.
 

·
Plain ole user
Joined
·
11,121 Posts
I assume you must be very technically proficient, as working on a power supply is very dangerous or so I read when experiencing problems with my old Panny plasma.

My vote: Buy a new TV & be done with it...I did.
There is good reason to attempt DIY repairs rather than discarding a set. It may, realistically, be beyond the capability of many to dig in and learn to solve a problem at either the board or the component level, but I applaud the individual willing to take on a challenge and learn something new. You may choose a different path, but many of us take pleasure in solving a problem and even at just learning something new while sending a broken product into a more permanent brick or boat anchor state.
 

·
Registered
Joined
·
8 Posts
Hello everyone! I'm a total newbie to TV repair, but I know a bit about electronics. I just had to register after seeing this thread.
I also own a Hitachi, but the model is a P50H4011 (also a 50" plasma, Canadian version should it matters :) ). A couple days ago, it just stopped working altogether: no sound or image. Just a blue light blinking 4 times repeatedly, and no way to shut down the TV save from unplugging it from the power outlet. I opened the back case and saw a puffed capacitor (3300uF, 100V) on what I assume is the power supply. I changed both to be sure with equivalent caps I ordered, but nothing changed. The TV is not hooked up to home theater system, so it kinda rules out common possible problems, but I'm still stumped. Does anyone have an idea on what to do next? Is there something that I missed? All help is welcomed. Thanks!
 

·
Registered
Joined
·
14 Posts
Discussion Starter #5
Hello Lurker, welcome to the forum.

Did you happen to check the upper and lower SDR boards, or buffer boards on the left side of the tv (while looking at the back of it), for any burn marks on the individual chips. You have to look close.

Do a search on this forum for the Hitachi p50s601 with 3 blinks and you will find the thread on how to check your SDR boards.

Good luck!
 

·
Registered
Joined
·
8 Posts
Thanks for the heads-up mvalent000! That suggestion was really useful!

I've re-opened the TV to check for busted chips, and I'm almost ashamed to say that I missed this: there seems to be a couple of chips with pin holes in them on the left side of the TV... Upon closer inspection, it's the SDR-U board that has all the burnt surface-mount ICs. Three of them! Obviously, I'll have to change the board, but now I have more questions for you guys:


-Is it "normal" that only one board went kaput? My thought was that if one is damaged/broken, then the other one is bound to be damaged/on-the-verge-of-dying.

-Assuming the other board is OK (along with the PSU), shouldn't I get the bottom half of the picture? I've read somewhere else that it was possible to get only a part of the image if the other board was OK. Has anyone of you ever experienced that?

-I saw someone on the *Hitachi P50H401 led flashes 3 times.* thread mention that the Hitachi service bulletin states that you should also change the Y-SUB card along with a defect SDR and PSU. Any truth to that, or am I overly cautious (read paranoid :) )
 

·
Registered
Joined
·
14 Posts
Discussion Starter #7
If you disconnect the SDR board with the bad chips and then plug in and turn the tv on, you will/should see the other half of the pic. It won't show the picture with the bad SDR board plugged in. You can just disconnect it from the Y board. Only do it for a brief time.

As far as the Y board being replaced with the buffer/SDR boards.........that's a hit or miss. I have a Hitachi 401 that all I did was fix the chips on the SDR boards and never replaced the Y board. I am still watching it without an issue (knock on wood). The chips were replaced last year.

So I can't give you any advice on what to do with the Y board. Maybe someone else will post about that.

For right now, get your SDR replaced, plug it in and roll the dice!
 

·
Registered
Joined
·
8 Posts
OK, update time!

I was able to remove the defective board, and plug the TV back to do a quick check. This time it went on and I was getting some sound. I could not however get any image, so I let it on for maybe 10 seconds, maybe it takes longer to get any kind of image since only half of the TV is kinda working...

POW!

Burnt smoke and the (unfortunately) oh-so-familiar smell of burnt IC in the morning, well, afternoon... :crying: Yup, my other SDR card now has a new redesigned top IC with a crater on it. At least it solves my first problem, so on with the questions:


-Has anyone ever had to change both SDRs and possibly the Y board? Any success, or am I getting on never-ending cycle of card-swapping for as long as the TV lives? :spend:

-Any dealers/resellers that you could recommend? I know that being in Canada is a bit more restrictive, but I'm willing to import the parts should I see a good deal. Speaking of deals...

-Any luck scoring parts with eBay? I saw a couple auctions, but then again, all dealers are US-based (expensive, thanks a lot UPS) or in China (reliable?)


I'll try to keep the morale up and the updates coming...
 

·
Registered
Joined
·
14 Posts
Discussion Starter #9
Oh that is not good! I did the same thing last year with mine.

I replaced both of my SDR's in one shot, it wasn't cheap, 120.00 on Ebay. They are currently working to this day.

Do an internet search.

Find someone that offers a good warranty, like 30 days.
 

·
Registered
Joined
·
8 Posts
Did you notice any change in the quality of the picture, or is it "like new" now? Or any other problem that popped up. I think a saw a couple of SDR boards for that price on eBay too. Looks like I'll need to send my credit card # to Hong Kong again...

Still deciding if I should keep putting money on it or call it quits and get a new TV though... It's not that old, around 4 years old tops, but I keep thinking that at some point it's just cheaper to just pick a new one. It's a shame that the components are so hard to get, and so easy to bust if I may add ;) . In any event, I'll keep you posted.
 

·
Plain ole user
Joined
·
11,121 Posts
Anytime you change parts, or with aging, the set may need some alignment. In many cases it may not be a significant difference, but it is hard to say. Be sure that you have the correct manual and be prepared to follow the procedures for service alignments.
 

·
Registered
Joined
·
8 Posts
Almost an update:

I've been hunting and searching locally for the parts. So far, the only authorized Hitachi dealer in the neighborhood (30 minutes away) no longer deals with Hitachi. No boards, no parts, zip. They even closed their service accounts with them... My only luck might be tomorrow in Montreal (70 minutes away...) to score the parts, SHOULD they have it stock. I can only hope that they won't gouge my wallet, but I'm not very optimistic. When you're asking for that kind of part, they know you're in trouble.

On another note, lcaillo et al, can you tell me where to get a service manual that explains the calibration procedure, or should I consider that Google is my friend ? Unless you tell me to search here, which I'll do once I post this... :)
Also, how long should I take to accomplish this task, since I'll be my first time messing around a flatscreen? The last time I played inside a TV they were called CRT, so... yeah :blush:
 

·
Plain ole user
Joined
·
11,121 Posts
There are links in the vendor listings for service manual dealers. You can often find them for free if you search, such as at elektrotanya. Try Shop Jimmy for parts.
 

·
Registered
Joined
·
8 Posts
All hail elektrotanya!!! Excellent suggestion to go there; definitely favorited!
I've took a quick glance at the service manual, but I don't like what I've seen. The Y-Sus might also join the club for broken parts that I opened not long ago... I'll need to call tomorrow to see how much this board is worth. It feels like this unit is heading for salvage. I'll keep you all informed...
 

·
Registered
Joined
·
8 Posts
Final update...

Impossible to order the parts locally. I need the "exact model of part with production #, since there is so many models"... My built-in translator returned "too much trouble, not enough profit, too lazy", or something along those line. So, after some thinking, I've decided to scrap the Hitachi. It hurts a little bit, but knowing that I need two SDR boards for sure, most likely a Y-SUS board with my luck (or lack thereof), plus some fine tuning/adjustment to get an image hopefully like it was before, I think it's better that way. In parts alone I'll spend +-220$, plus the 23$ for the busted caps, not knowing if I'll get a good picture. For 700$ + taxes, I'll get a brand new LG 50" plasma 1080p (instead of 1080i with Hitachi) with an extra HDMI. I know my wallet will hurt whichever way I go, so this time I'll go for the brand-new option. With what I "save" from parts, I'll splurge on a UPS to prevent this from happening again. Some lessons are more expensive than others...

Anyway, I'd like to thank y'all for helping me out. I learned some stuff along the way, so I guess all is not lost. I'll try to hang around, and maybe I'll have some more questions for you in the near future. Thanks for your time, and sorry if I derailed the original thread a little bit ;)
 

·
Registered
Joined
·
14 Posts
Discussion Starter #17
I started this thread and it turned into a buffer, power supply caps posting. I would love to get it back on track with the 4 blink issue that nobody seems to know what is going on.

In a process of elimination, I have been able to power the tv on with the plug that goes to the logic board unplugged. The tv will power on and stay on until I plug that plug back in. When that happens I get a quiet high pitched sound coming from the upper middle right of the power supply and then it shuts itself down.

Now the blue led light stays lit and does not blink.

Keep in mind that I have 2 of these 601's that are doing the same thing! Caps have been replaced and IC's have been replaced.

Running out of patience and room with these 2 tv's. Any help would be wonderful!!!
 

·
Plain ole user
Joined
·
11,121 Posts
New problems should be placed in new threads with the model and issue in the subject line.

A high pitched squeal from a PS almost always indicates that it is working hard to drive an incorrect load. Usually a short somewhere downline. I would be looking for a shorted component on whatever circuit that PS section is feeding.

When you say you disconnected the line to the logic board, this really does not tell us very much. Exactly which board are you disconnecting from the logic board?
 

·
Registered
Joined
·
14 Posts
Discussion Starter #19
This isn't a new problem, it's a continuation of the original 4 blink issue.

pin CN68 on the power supply is the plug being unplugged that goes to the logic. Now if I plug CN68 into the power supply and the logic board and then unplug the big clipped in ribbon cable on the logic board CN01 (that goes to the pre-AV board) then the tv will stay on.

I went through the service manual with some of it's confusing things to unplug and bottom line, I am not getting the correct VA and VS voltages from the power supply. The Vcc is reading correctly but nothing else.
 
1 - 19 of 19 Posts
Top