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Hello shack, firstly I want to thank you all big time for such an invaluable site here. I have learned a lot since yesterday just from reading as many threads as I can find on this style of TV.

I will try to keep this as clear and concise as I can.

I was on vacation for 6 days, and came home yesterday ready to kick back and watch the bigscreen. Turn it on, and the red horizontal convergence was way off (was perfectly adjusted when I left). My roommate says that it was working fine for the superbowl the day before, and I have no reason to suspect that he did anything out of the ordinary to it.

The basic overall convergence can move both ways on both red and blue. When switching to the "advanced" red convergence adjustment, the lower/right portion of the screen is off by over an inch to the right, and will not move back to the left whatsoever. Vertical adjustment works fine and can be dialed in.

I removed the front screen to see what I could see, and everything appeared normal. That is, until I looked directly into each projector with the set on. The red gun looked rather blurry overall, and the lower half of the picture looked almost scrambled, in a manner which I can only describe as horizontal interference lines. I tried the AV reset, the system reset, then tried to reconverge again. If I center the red using the basic convergence adjustment, the red part of the picture starts to get very distorted and the horizontal interference is noticeable on the screen itself. Switch to advanced and the red is now off-line all over the screen. :rolleyesno:

So I fire up the laptop and start hunting for info. I see a lot about the convergence IC's and what happens to them, but I never see anyone describing the same interference in the red gun that I am seeing. I am wondering if I have a different problem with the red projector, or if this is simply another symptom of the IC issue.

My best friend is a electronics wizard and has tons of experience with soldering chips and boards, so I decide to open up the back panel to try and get the board out to take to him. I was seriously ashamed of how dusty it was in there... everything was CAKED with at least a half inch thick layer, tons of cobwebs everywhere, just overall a nightmare. I cleaned it all up with a can of air, and it all looks brand new now. No signs of coolant leaks like I had read about. Thinking that maybe it was all the dirt causing the problems, I fire up the set to check. Same problem.

I then pull several white harnesses to free up the board, pull it out so I can now actually see the IC, and then it hits me that the TV may be down for quite awhile before reassembly. I figure it might be a good idea to plug it all back in and take some detailed pictures in case I need help with where the different wires go. I also wanted to take some pictures of the screen itself for getting help with any additional diagnosis. Plug all the white harnesses back in, but one seems to be missing in the back left corner... there is a spot on the board for a harness to plug into, but I for the life of me can not find a harness to plug into it.

I plug the set in, and now I have the continuous green light of death. :hissyfit:

So that is where I am at now. My questions are as follows:

1. Is it possible that my issue lies in the red gun and NOT in the convergence IC?
2. Is it possible that the continuous flashing green light is caused by that one white harness not being plugged back in? If anyone is familiar with this particular set and can tell me whether or not that plug is supposed to be empty, you would be my hero.
3. How did this likely happen in the first place? Is it just random (bad) luck that it happened while I was out of town?... or is it likely that my roommate did something to cause this?

Any help or guidance would be GREATLY appreciated. I have background in mobile electronics and have done standalone engine management wiring, and just overall a DIY-type person when it comes to just about everything. I have also done a lot of stereo installs, so I am not completely inept when it comes to electronics, but RPTV's is a realm in which I have never dabbled. I purchased the service manual, and tried to contact a repairman that might be able to help. Being here in New Mexico usually creates a problem when trying to find good help, and this case is no exception. I would much rather attempt to fix this old box myself first before making 2 hour trips and paying several benjamins.

Thank you again for any insight.

-Rich
 

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Assume it is the most obvious things first. Change the convergence IC and the caps in the DM. You often do not know about the DM caps being bad until you unplug the set and it has to reset.

Did you read the convergence repair thread?
 

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Discussion Starter #3
Assume it is the most obvious things first. Change the convergence IC and the caps in the DM. You often do not know about the DM caps being bad until you unplug the set and it has to reset.

Did you read the convergence repair thread?
Yes I did, and thank you kindly for that thread. :kiss:

I guess really, I come from a little car world that hates just throwing new parts at things in an attempt to fix issues. If that is what must be done in this case since I do not have any diagnostic equipment, I totally understand.

However, I was hoping maybe someone would read the description of my symptoms and know exactly what was going on. I've got all the part numbers here and ready to order, but if it's something as simple as that one harness not being plugged in, I would rather not buy parts that I won't need. :yes:
 

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With the service manual, did you confirm that you had all the cables plugged into the right fittings? You mentioned that you had one fitting without a cable going to it. What did the service manual show?

Its pretty much a given that you have an IC problem from your early description of the display.
 

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Discussion Starter #5
With the service manual, did you confirm that you had all the cables plugged into the right fittings? You mentioned that you had one fitting without a cable going to it. What did the service manual show?

Its pretty much a given that you have an IC problem from your early description of the display.
Yes I am actually going over the schematics right now, trying to figure out whether or not it should be empty. I did figure that the original issue was with the IC, but the horizontal fuzz I was seeing in the lower half of the red lamp worries me since I haven't read about that anywhere yet. If it is just another possible symptom of a bad IC, I would be relieved because that repair seems very doable for me and a buddy.
 

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Ok just as a quick update, I have confirmed on the schematic and from a few pictures I found online that there is no harness plugged in to that clip.

Thank you Leonard, I believe that you were right about the flashing light not coming up until after I had unplugged the set.

I will order the new IC and the DM caps. Is there anything else I should do while we have the boards out? Any other preventative maintenance or anything? Lastly, would someone be kind enough to walk me through, or direct me to a thread that might already have the info for tuning the set after it is all repaired?

Thank you guys again.
 

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Yes I did, and thank you kindly for that thread. :kiss:

I guess really, I come from a little car world that hates just throwing new parts at things in an attempt to fix issues. If that is what must be done in this case since I do not have any diagnostic equipment, I totally understand.

However, I was hoping maybe someone would read the description of my symptoms and know exactly what was going on. I've got all the part numbers here and ready to order, but if it's something as simple as that one harness not being plugged in, I would rather not buy parts that I won't need. :yes:
I agree 100%, if I had the set in front of me. Someone might, but without being there to see the symptom and do some troubleshooting, my experience is that if you don't have the troubleshooting skills to not have to ask, it is a big waste of time to do much more than symptom-repair shotgunning. The time wasted by just a couple of jobs where I try to step by step take someone through a repair would keep me from helping anywhere near as many people as focusing on high % probabilty symptom-repair relationships. It is simply beyond the scope of the forum.

The fact is that the two symptoms you describe are very likely what I suggested, and even if yo buy the parts to try it, you will have less in the job than an estimate by a qualified tech.

There is an old saying that if you hear hoofbeats, think horses, not zebras. No guarantee that it is not cattle, but then that is what an experienced tech would see right off with a few checks that are routine to us, but could take days to talk someon through.
 

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Ok just as a quick update, I have confirmed on the schematic and from a few pictures I found online that there is no harness plugged in to that clip.

Thank you Leonard, I believe that you were right about the flashing light not coming up until after I had unplugged the set.

I will order the new IC and the DM caps. Is there anything else I should do while we have the boards out? Any other preventative maintenance or anything? Lastly, would someone be kind enough to walk me through, or direct me to a thread that might already have the info for tuning the set after it is all repaired?

Thank you guys again.
There are several sites with information about tweaking your set. If you have a question, just ak here, but I do not have a step by step process for your set.

The other things that you need to do are to clean the lenses and mirror, resolder any joints anywhere (but particularly on heat producing components) that look marginal. have ring cracks, or are powdery-gray looking. Be sure to get all the wires dressed exactly like before, do the convergence and focus adjustments and whatever picture adjustments you are capable of doing or calibrate the set.

First worry about fixing it. Use the suppliers recommended and only first rate parts.
 

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Discussion Starter #9
I agree 100%, if I had the set in front of me. Someone might, but without being there to see the symptom and do some troubleshooting, my experience is that if you don't have the troubleshooting skills to not have to ask, it is a big waste of time to do much more than symptom-repair shotgunning. The time wasted by just a couple of jobs where I try to step by step take someone through a repair would keep me from helping anywhere near as many people as focusing on high % probabilty symptom-repair relationships. It is simply beyond the scope of the forum.

The fact is that the two symptoms you describe are very likely what I suggested, and even if yo buy the parts to try it, you will have less in the job than an estimate by a qualified tech.

There is an old saying that if you hear hoofbeats, think horses, not zebras. No guarantee that it is not cattle, but then that is what an experienced tech would see right off with a few checks that are routine to us, but could take days to talk someon through.
:T

I agree and thank you again for your guidance. I appreciate it big time.

There are several sites with information about tweaking your set. If you have a question, just ak here, but I do not have a step by step process for your set.

The other things that you need to do are to clean the lenses and mirror, resolder any joints anywhere (but particularly on heat producing components) that look marginal. have ring cracks, or are powdery-gray looking. Be sure to get all the wires dressed exactly like before, do the convergence and focus adjustments and whatever picture adjustments you are capable of doing or calibrate the set.

First worry about fixing it. Use the suppliers recommended and only first rate parts.
I will do all of that, thanks. Already got the IC and caps on the way from the recommended folks, although it looks like it will be next weekend before my buddy can make it down here to help with the soldering.

I'll take lots of pics and post up how it went.
 

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SUCCESS!

Replaced the DM caps, replaced the IC, baby fired right up. Quick convergence adjustment, and she looks as good as ever. Total tally... 8 for DM caps, 28 for the IC, 80 tip to my buddy for driving all the way down here... so 116 bucks versus the 1k+ I was quoted by both of the mitsu authorized repair shops here.

Thank you all again!

If anyone ever needs detailed pictures for this model in the future, I would be happy to provide you with any of the several that I took.
 

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The fact that you were quoted over $1000 to repair this set by two different ASCs is a disgrace and a good example of why I help DIYers like yourself. The repair business has a well deserved rotten reputation, and shops like this make it worse. I suggest that you name the shops and give the details of their estimates publicly.
 

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The fact that you were quoted over $1000 to repair this set by two different ASCs is a disgrace and a good example of why I help DIYers like yourself. The repair business has a well deserved rotten reputation, and shops like this make it worse. I suggest that you name the shops and give the details of their estimates publicly.
Both shops are in the Albuquerque area.

Crown TV and Electronics -

No house calls for repair work.

Diagnosis - 125
Convergence - 350 to 600 depending on the part needed
Flashing light - 800 for DM board replacement/repair

Five Star Electronics LLC -

No house calls for repair work.

All inclusive rough estimate of 950-1200 depending on the parts needed and the diagnosis time spent.


..............................................................

I called 7 different places and these were the only 2 that would even touch this set. Both of them made it seem like it would take them countless hours for diagnosis. I also was not too happy about figuring out how to lug the entire bottom half of my 65" down to them in my small car, haha.

Needless to say, with estimates like those, I was immediately researching new sets. Glad I found this site before pulling the trigger on one. :hail:
 
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