Samsung DMD board replacement - Page 2

How did you get the Lamp time ?
I am sure there is some code on the remote that will tell you this, but I have been unable to find that.

My unit was not used much , ie also babied and well ventilated. I had it plugged into a surge protector.

Re: parts: some of the parts places with Samsung parts will give you a list of parts, or better yet put in a part number and they will tell you the samsung units that this part will work with. Try part BP96-01626A on SamsungParts.com or PartStore.com

When I talked to Samsung America about the incorrect part number they had originally told me was for my unit, they stonewalled me. I only found the new part from PEZjunkie on this forum ! Pretty terrible customer support !

naseqp-

be careful replacing the light engine - it can run about 900$. It the same labor charge because they can easily throw in the light engine assembly which is like on a platform.
Whereas dismatling the DMD board and DMD panel ( the micro-miror assembly) which are components of the light engine is time consuming. So it is easier for them if they just charge you for the more expensive part !

Thanks to PEZ I was able to put in the access code for the service menu.
My machine has 1065 hours in the lamp.

FYI there is another forum that discussed alot of Samsung problems:
http://forum.ecoustics.com/bbs/messages/2/77447.html

I found only one case of the white spot problem we seem to be having, but alot of discontent about Samsung quality and service.

Also found that there is a class action suit against Samsung re: shadow effects in their rear projection TV's.

http://www.samsungtvshadowclassaction.com/main/home.sfx

In looking at the complaint it could easily be our problem ! I can see why Samsung is adamant in not helping us after the warrantee is out. Any help would be viewed as an admission of guilt or an acknowledge they were or are aware of the problem, etc.

Hey that looks just like my screen !

Also I confirmed that discharging all the electronics over night did not change the location of any of the white dots on the screen. No question it is the DMD panel ( micro-mirror assembly).

In regards to who to contact re: class action, there are three firm involved. I have sent an email to Lax already. It may be best to convince one firm that there are a number of folks with the same problem. Send me you email address by private message and I'll forward you any responses, etc.

I have also sent a complaint into TI who manufactures and sells the micro-mirror chip as well as to an engineer at Samsung in Korea. Heard nothing yet.

The one Samsung authorized service company I talked to was pretty friendly and open. They told me that Samsung recomends that the entire light engine assembly be replaced. I suspect that is true for all repairs done under warrantee. While this component is expensive to us, I'll bet that Samsung doesnot reimbuse their dealers for the full price of parts. But Samsung has to reimburse for full time and labor of the repair.

It appears that most models with this problem as best I can recall are the HLS series, and version PB02. This includes 42" to 50" units.

Anyone new or posting to this board should identify their TV's model and version numbers , and hours on the lamp so that we can define a list of units with this problem. One thing I suspect is that the PB02 versions of the HLS series arose from a problem they had and the new version was intorduced with a different DMD board and color wheel controls. (Pez's documentation mentioned that the DMD board in the PB02 units cannot be replaced with the PB01 DMD board, since the DMD board controls the synchronization with the color wheel and is different in the original vers new DMD board. That's probably another reason Samsung recomends replacing the whole engine assembly!)

I talked to the Attorney working on the Samsung " Shadow"class action suit and he is very knowledgeable about these rear projection TV's. He said he'd be willing to incorporate this problem in the existing suit, but he has not heard of this problem eventhough he claims to have talked to thousands of people ( probably an exaggeration). So I volunteered to send him further information.

So if any of you have found web sites with people complaining about this problem please post it or send me a private message. If you send me your email I will copy you on all correspondence with the attorney.

Also, posting more titles with descriptions of the problem in different terms, eg, white spots, starfield, white specs may lead to more folks find our discussion group.

Here are the HLS models that are discontinued:
http://www.dlptvreview.com/dlptv/samsung-dlptv.html

I found this in a thread about the "shadow" problem. It may provide an extended warrantee in your TV purchase.

" purchased my HLR-6168W back in August 2005 and had a flawless picture until January of this year when the dreaded "shadow" problem appeared (nothing big, just a 1.5" shadow along the right side of the screen. After finding this thread, I called Samsung the next day. Found out at that time I was six weeks out of the 12month + 3 additional free months Samsung manufacturer warranty. Samsung CS eventually gave me the "sorry we can't help you" response. I still tried my best with their ECR people numerous times and got rejected by them as well. Fortunately I purchased the unit using my Visa card that doubled the manufacturer warranty. So I went through them a few months later and in August finally had the entire Light Engine replaced (even though my shadow never got any bigger from day 1). When the service guy came out to replace the LE, I got lucky and received a brand new light engine instead of a rebuilt one and once again everything looked good as new."

Here is the Visa warranty website:
http://usa.visa.com/personal/cards/b...ranty_mgr.html

Pez- Good point about the part numbers differing. Clearly the lens and the light tunnel will differ depending on the set size. The DMD board version is critical since that changes the synchronization with the color wheel. I'd expect each screen size to have a different imaging plane ( distance from micro-mirror to the lens) so that the entire light engine assembly would placed a slightly different distances to the screen inorder to fill the screen.. That would require they have different part numbers.

Given the similarity of failures, I'd bet the DMD boards and DMD panels ( micromirrors ) are the same... The question is why are some units, ie our units failing ? Is it a bad bunch of TI micro-mirror chips? or did Samsung screw up on the heat dissipation and the cooling of the chip is not sufficient depending on , for example, how the cooling fins were installed.

One thing I was thinking was whether corrosion of the contact may be a source of the failures we are seeing. That means that the micro-mirror and actuators are okay and need not be replaced. Let me explain....

In the SW region of Fl where I live the water is very sulphurous, and you get alot of hydrogen sulfide ( rotten egg smell) coming out of the water and into the air. This was certainly the case where I had my TV. The dissolved hydrogen sulfides in the water also tarnishes silverware pretty rapidly.

The contact pads in the DMD board are flat - no holes that the pins sit into. So if there are any differences in pin heights the degree of contact and pressure of the pin to the pad will vary. The pins with the least contact are weak points that can later fail if something can phyically "attack them".

If these contacts are not coated/protected with some anticorrosion coating after contact is established but left exposed to the air, then the corrosion of some contacts on the micro mirror could reduce the operating voltage needed to get the actuators to operate the mirco mirrors. On the board I had it looked like the contact board looked like copper pads. I am not sure whether these are copper-silver alloy or pure copper pads, and whether copper corrodes as fast as silver. (Silver may also be intoduced to get the solder to flow more readily)

Note that in PC's all the circuits boards are coated to avoid external corrosion sources. The drives hermetically sealed too. The only exposed contact are probably the keyboard switches and they are not logic elements that require precise operating voltages ... .

The cure to this problem is to take out the DMD panel and very carefully clean the contacts with some silver tarnish remover that removes the sulphides. This would consist of putting the solution on an optically flat surface and gently rubbing the DMD contacts along this surface. Also rubbing the surface contacts on the top of the DMD panel with the solution. Note that the micro-mirrors on the DMD panel probably have anticorrosive films on them from the normal VLSI processing. I would be VERY careful to avoid any contact of the solution with the mirror side of the DMD panel.

I can understand why Samsung may not want the Service folks to try to clean these contacts with a solution. These solutions act to etch the surface and may ruin the micro-mirrors if spilled on them. ( Further from what I've read after dissassembly of the DMD board and DMD panel it is pretty tedious to get all the parts aleigned right so as to get the picture centered on the screen.)

To verify whether this Hypothesis is reasonable, I think I'd try to determine whether the fan that cools the DMD panel is working properly by opening the case and running the unit, turning it off and then feeling how hot the DMD panel heat sink is. If it is hot - like 60 degrees C- it is an over heating problem. If it is just warm then it could be the contacts...and if these contacts get warm - like 40 degrees - the corrosion will be accelerated.

I just contacted visa and my card qualifies for their extended warrantee !
So I lucked out !

Once they process my claim and I see what they do, I'll either have a repaired TV or they will reimburse me what I paid for the set. If it is a reimbursement and they leave me with the set, I'll probably resume work on it.