Samsung HLT5075SX/XAA lamp overheating

[toolbox978]

Hello,



I have a 50" Samsung HLT5075SX/XAA DLP that recently had a bulb go out. I ordered a nice OSRAM replacement, and within 2 weeks that bulb went out too. I recorded a video of the tv trying to fire up the burnt out lamp and uploaded it to YouTube [url=https://www.youtube.com/watch?v=jXqApBNaY4Y]here[/url]. You can see the bluish light of the ballast trying to light the lamp, and a loud noise associated with it, but clearly won't. All 3 lights blink on the front simultaneously indicating a bad bulb while the tv cycles on and off repeatedly.



So upon returning the lamp they said that the small wire protruding from the arc tube was oxidized, and that it might be a bad ballast or fan causing the problem. They had me inspect the capacitor on the ballast to see if it had puffed up or blown out a little bit, and that is not the case.



I'm led to believe the problem still might be the ballast, but if possible I'd like toe be sure that's the problem first before spending the money. Are there any other steps I can take to help diagnose this problem? Could it be anything else? I found a thread on this forum [url=http://www.fixyourdlp.com/forum/viewtopic.php?f=10&t=6392&p=12487&hilit=hlt5075sx#p12487]here[/url] that says it is not possible to test to see if the ballast is the problem without trying a new one.



Thanks for your help.

[grayfox]

Hello!



Thank you for the detailed explanation and video, it helps with the troubleshooting. And let me tell you this is the number 1 problem with DLP televisions, I want to say 90% of the time its the lamp and 10% the ballast, but it varies from tv model to manufacturer and condition of the set. Either the ballast might be too weak to spark a new lamp or the new lamp is defective/generic.



The arching we see on the video is in fact the ballast attempting to ignite the lamp and failing. Unfortunately you are correct, you cannot test it for certain without having a replacement lamp/ballast.. Since the ballast takes a few more steps and (in my experience) many times it turns out to be the lamp, I would begin with trying a new lamp instead. Reason being that to begin with, Samsung TVs use a Philips brand bulb not an Osram. And secondly, both Osram and Philips are very exclusive about their providers, hence there are very many bootleg and counterfeit lamp sellers out there.



In short my initial recommendations would be to order the original Philips lamp, you can order by your model code BP96-01653A for that TV. You do not have to go straight to Samsung, there are many retailers that offer original Philips, I normally order from www.discount-merchant.com and when out of stock on what I need I head over to www.discounttvlamps.com The reason I mention these is because if you order the Philips, you can be sure you will receive an OEM lamp..



Can I ask where you purchased the Osram lamp?

I hope I can be of further help!

[toolbox978]

Grayfox - thanks so much for the very helpful, detailed reply. I purchased the OSram bulb from a distributor on [url=http://www.amazon.com/dp/B0019FLXWO/ref=pe_385040_30332190_TE_3p_M3T1_ST1_dp_1]Amazon[/url]. They have also been extremely helpful.



I'm tempted to buy a new ballast anyways, if I can somehow get another 5-6 years out of this tv that would be amazing.



Thanks again,

Mike

[toolbox978]

[toolbox978]

Ok so I put the new lamp in with the old ballast, left the chassis off to ensure max airflow was getting in/out, and held down the chassis switch with my finger while i turned it on, and got a picture.



I'm nervous to leave it on for fear the bulb will burn out again in a matter of weeks. Could the ballast still be the problem, or should I try installing an additional fans? This tv is 100% free of dust.

[toolbox978]

Ordered a new ballast anyways, was ready to put it in, but wanted to test the power it was getting to make sure that's not the cause of it overheating



The [url=http://www.scribd.com/doc/120923694/hlt5075s-service-manual]service manual on page 56[/url] indicates that part CN801 on the Power Board should be supplying DC330V+/- 10% to the ballast. Using a voltmeter it read approximately DC313V, which is within tolerance. And I'm still getting the blue arc that I need. So I still can't figure out why my lamp would be overheating.



I also ordered a [url=http://www.newegg.com/Product/Product.aspx?Item=N82E16811999130]Thermaltake Mobilefan II 80mm External USB Case Fan[/url] and plan on fixing it to the intake/exhaust to increase airflow.



Think I should replace the ballast, or is my old one ok?

[grayfox]

Increased airflow, as you know, will always optimize electrical equipment lifespan.



If your old ballast gives you a bright picture, have you considered leaving it installed and putting the TV back together? maybe you can get some use out of it that way? then when the time comes you can replace this with an OEM lamp and a new ballast! Just a thought. Let me know the status of your TV and I hope I can be of any help.