Question about Sceptre X37sv-Naga 37 in. LCD Television
Our 1.5 year old Sceptre X37SV-Naga suddenly stopped working today during a lightning storm. I took it apart and found a short circuit between two small capacitors adjacent to the 110volt power cord input to the power supply board. Any one else had this problem? Anyone have a wiring diagram? Do you think this problem would be fixed if I simply replace these two capacitors that are arching? I had this problem many years ago with a B&W TV and replace one resistor that blew after a storm and it worked perfectly afterward. What say you experts? Thanks for your help. MJK
I have the same problem. TV was JUST out of warranty. Sceptre part number is X37SV-Naga and the cost - $285.00 plus $20 shipping. Non-refundable, no returnable.
The TV is of course going to de-solder the board within a year again, so either a good heat sing on both thermistors is in order OR a law suit against Sceptre is in order for putting us a risk of fire.
Posted on Jul 09, 2008
I posted above with the pictures. Frank Reed has it right. I did the same thing, soldered those two thermistors back together on the underside of the PCB and it turned right on. Then it died again after a week, and I realize I didn't solder them well enough. You have to get that PCB foil in there, because it is bringing current from another component. So I just really gobbed the solder on there. It hasn't given me trouble for months. I bet this is the major reason these TVs go bad. I should start buying inexplicably broken ones, fixing them and selling them.
Posted on May 02, 2008
Frank, do you think it's possible for those thermistors to get hot enough to actually catch fire? I am considering installing a small 12V fan to cool them off. Do you think this is necessary?
This is an ancient post but I thought it warranted clarification for the future. The typical arrangement is one thermistor in series with the AC line, the other similar-appearing part is across (parallel) to the AC line. The first limits inrush current, the second peak voltage that can appear in a line surge; this part will fail by design at a design voltage an cause the fuse to blow preventing fire but not internal damage to the appliance.
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Had the same problem - TV was on and then just quit. SCK-85 thermistors had overheaded to the point that their input side unsoldered from the pcb. Actually part of the pcb foil was damaged on the AC input side by the heat. Checked the resistance and thermistors appeared to be okay, so resoldered them and TV is working at the moment.
Appreciate if anyone knows of a more reliable thermistor. I don't have much confidence that this problem won't recur in the future.
Frank Reed, [email protected]
Posted on Jan 01, 2008
I have the same problem. They are not capacitors but thermistors. They are manufactured by Thinking electronics in China. They are SCK-085. Problem is - I cannot find a 13mm 085 in the catalog. Only 15mm. I order a few - will see if this fixes the problem.
Posted on Oct 04, 2007
Pwor suply shot
Posted on Mar 23, 2013
I had the same problem recently with my 3 yera old X37 from COSTCO, and when I saw the photos and posts here, I opened up the set, and sure 'nuf, the thermistors had 'unsoldered' themselves. Instead of using regular rosin-core electronics solder, I used silver-solder and the appropriate flux (usually used for plumbing, since it is lead free), which has a higher melting point than lead-tin solder. 4 months later, no problems.
Posted on Feb 15, 2009
Wow, gotta say: this page is excellent. My TV died this morning and I only got to fixing it tonight, found the bad thermistor(s), got on Google to find a replacement and found this site.
My contribution to this site is the following: My TV is branded BenQ not Sceptre. The pictures above are an EXACT match it is also a 37" LCD. Not sure if BenQ is using the same power supply or if one or the other company purchased each other, who knows.
My TV has run problem free for almost 3 years. I'm going to resolder the components and see how many more years I can get.
Posted on Aug 30, 2008
I'm so thankful to have found this website as I had the same problem as others with the overheating and a thermistor had become unsoldered. Cleaned and heavily resoldered and it's working great again! Not sure how long it will last but..... Thanks so much for the pictures, it made it possible for this novice to get it going again!
Posted on Aug 23, 2008
Hi all,
Had this same problem and used the following parts to fix:
From Mouser.com...
871-B57238S100M
EPCOS NTC Thermistor
10 Ohms 5amps 3065k
From Home Depot...
GE Silicone II
Posted on Jun 16, 2008
Hi all,
I have the same problem with my X37. There was arcing underneath the Thermistors, so I unsoldered them and tested them with a multimeter. One of the thermistors was busted (the reading was going down when I heated it up by pressing my soldering iron onto it). I have ordered some replacements from mouser (they are super cheap to find, but shipping was a pain). The goop in the middle is some sort of thermal caulk - i've read that GE Silicone II can be used for this purpose or heatsink epoxy. Anyways, will update if I am able to fix this. Thanks for the pics above.
Posted on Jun 10, 2008
Yet another X37 with the same problem. Mine has failed twice. I thought maybe my soldering job wasn't so good first time around so I was careful this time to make sure I have nice wet joints. However I believe this is a recurring problem. For what it is worth, the SCK 085 is a current limiting device called a Varistor (variable resistor). Apparently it does come in different current ratings, the problem is identifying the ones that are in the X37. (Bear in mind that they have to be rated for 250V also.)
Metal oxide variable resistors (movistors) are common in surge protectors. In the absence of any assistance from Sceptre, we should be able to locate a suitable replacement.
Posted on May 19, 2008
I've been thinking about this some more. I suspect the problem with the X37 power supply is specific to the Americas with the 120V power supply. The rest of the world uses 220-240V and would draw less current to deliver the same power. Since heating is more a function of current flow than of voltage then lower voltage -> higher current -> greater chance of overheating.
As I see it right now, the main stumbling block to a permanent solution is my inability to discover the characteristics of the SCK 085 varistor. The device offers protection against transient overvoltages and I don't want to sacrifice that protection in a replacement device so knowing the specifications is important.
Meanwhile I did have another thought which I shall post for consideration and comment.
I wondered about the purpose of that the white gunk between the two varistors. If it is a (really good) heat conductor then it probably serves a useful purpose, but if it is not then the devices would be better off without it. What is the chance that it is heat sink compound? And how good is that stuff in such vast quantity? I always thought heat sink compound was only ever intended to be used in very thin layers.
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Update from Frank Reed: Since I bought my TV from COSTCO I went to them when Sceptre wouldn't communicate with me about the problem. Sceptre responded almost immediately after COSTCO contacted them. Sceptre was willing to repair the board, but was not willing to offer what I would consider a permanent fix - thermistors that would carry the required current without overheating and desoldering themselves from the PCB. I tried to come up with replacements on my own, but struck out, so I went back to COSTCO. At that point, the TV was working fine, but the COSTCO floor manager made an excellent point - "we can replace your TV, but we can't replace your house if the TV catches fire". I let COSTCO replace the TV. I had no complaints with the TV other than I couldn't trust it no to burn me out and electronics do occasionally catch fire, so good luck to everyone that has the Sceptre. Frank Reed
Posted on May 06, 2008
That would be a good start. remember that capacitors can store enough energy to shock or kill you.
Posted on Jul 11, 2007
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I have the same problem with my sceptre x37sv-naga. I plug it in and nothing, no power. Tried different cords. Where can we get these power supplies? What do they run $? Has anyone found a solution aside from paying for a $repair-man$?
Same problem - I checked the SCK-085 thermistors on the AC in and found that the thermistors had overheated to the point that they had unsoldered themselves from the pcb on their input side. I checked the resistance and the thermistors seemed good, so I resoldered to the pcb. TV is working fine right now.
Perhaps someone can tell me if more reliable thermistors are available. I really don't have much confidence that they won't overheat again and I'll have the same problem again some time in the future.
Frank Reed, [email protected]
Yeah I think I have the same problem. I bought it used two weeks ago, and it was working fine. I've had NO problems with it until today. Kaput. Walked out of the room to get some water, and when I walked back in, it was dead as a door knob. I unplugged it and tried a new cord. I heard a crackle, which made me think it was a short, so I popped the case and sure enough, I see brown on the plastic next to two round doodads with some kinda foamy glue between them. Best I can guess is they are thermistors.. it says NTC3 right next to them. I called Sceptre to try to get them to ship me a new power supply board, but I just got their voicemail. I'm sure it will cost me both arms and a leg though. I'd like to take a shot at fixing it myself if I can.
I've included pictures of the front and back. If I hack these off and solder new round thingies of the appropriate type back on, what do you think my chances are? Does this kind of damage make it likely that something else on the PSB is the problem? Please let me know if you need any more info or pictures? I am open to anything, seeing as how I can't break the PSB anymore, and I think I can get another one. [email protected]
Sean
Oops, I forgot to include these. Thanks, guys!
Just ran into this issue. Is the Sceptre power supply something standard or unique to the sv-Naga 37? I am willing to do some parts replacement, but I want to be prepared for the worst.
yes,My sceptre x37sv-naga 37 in. lcd tv have the same problem.
Thank you all. I have the same problem. I've had the tv for about 1.5 years. Sceptre definitely deserves a law suit.
looks like I have the same issue... I'll check the board and see. This is a great thread. Â I bought mine at Costco...looks like they will get a call from me soon.
Thanks everybody for detailed description and pictures. I just had the same problem - my Sceptre TV died right before the Thanksgiving. Luckily I found this site - otherwise I wouldn't have had any idea what to do. I opened the TV, found the power block, and sure enough saw that soldering was burned out in these exact two thermistors. I know nothing about electronics and soldering, but pictures were clear enough. I asked coworker who is good with this staff to solder the contacts for me - and it fixed it - I can now watch my TV again !
Thanks everybody for detailed description and pictures. I just had the same problem - my Sceptre TV died right after Thanksgiving. Luckily I found this site - otherwise I wouldn't have had any idea what to do. I opened the TV, found the power block, and sure enough saw that soldering was burned out in these exact two thermistors. I know nothing about electronics and soldering, but pictures are clear enough. I'll ask someone who is good with soldering to help me. I want to be able to watch my TV again !
there is a short somewhere but im not sure where
i have a short somewhere near the power supply but im not sure where
Thanks to all of you for contributing. Â I had the very same problem, so based on your notes I opened it up and checked the thermistors. Â Sure enough, they had desoldered themselves. Â Resoldered them and the TV came back to life. Â Thanks for putting this info out where people can find it.
Wow! That was exactly the same problem I had with my Sceptre 37" NAGA.
And I fixed it just as you all described. Thanks a million!
my sceptre had a fuse blown in it fixed that. over on the cooling plate is a resistor its blue, its behind transistor k3265 does anybody know what the resistor is and where i can get both? thanks iam new on this. R26 is the board number.
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