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Desertmariner
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No picture or sound, lamp cycles on and off

Post by Desertmariner » Mon Apr 05, 2010 1:37 am

Mod. HL R4667W
HLR4667wax/xaa
Type AT46L6
Mfg date 1/06
L64C
S/N Blou3cma100770z
Hi,new to this forum and i've read tons of good stuff. I wonder if i can use a phillips bulb even though OSRAM is written all over the rear of the set.

The t.v. is in-operative at this time. Light at front flashes You plug it in and the Projection Bulb comes on and is lit for about 5 seconds. It then goes out and will seem to cycle up for 16-18 seconds. You can hear and see the capacitor in the rear of the ballast board charge up (blueish light) for about 3 seconds.
Will cycle again and again. Same deal.
No picture, no menu. Nothing.
Fan behind DMD works o.k.
Fan at digital board doesn’t turn on.
I don’t think I hear the color wheel ramping up or off
I see two lights on new p.c.board from rear.
Cover switch is working fine and jumpered

History: worked o.k. for about one year. Started to shut down unexpectedly. Maybe you could get it to come back on remotely or manually.
Replaced the bulb with OSRAM brand bulb. The unit is clearly marked OSRAM on the DMD and the Ballast.
Still no work
Tech brought out and said the main board was defective. Paid 200 bucks and said goodbye. Bought board(with all the plug ins on the back) from Discount Merchant Vender on-line. Installed and
Still no work.
Previous owner gave up and now I own it.

Possible solutions,
Temp sensor is defective somewhere
Replace Ballast board which is located below the bulb housing.
Replace the DMD
Replace the color wheel.
Use for anchor on boat
Thanks for any help....I'm pretty handy and can wade my way through most of the tasks to repair.

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ChubbsTech
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Re: No picture or sound, lamp cycles on and off

Post by ChubbsTech » Mon Apr 05, 2010 5:36 pm

Hello Desertmariner.
Have you reset the lamp timer? First discard the easiest solutions to make way for the more complicated ones. If you’re not sure on how to do it here is the link to that post:
http://www.fixyourdlp.com/forum/viewtop ... ng+Factory
As for the bulb, yes you can uses a Philips lamp instead of a OSRAM as long as it’s the same wattage and you’ll have no problem at all (I highly doubt it the lamp). The digital board fan on the other hand is a abnormality that might be causing the board to overheat. So you might either fix or replace the fan. If nothing then it’s a strong possibility that the board is already fried. Another possible solution that you mention is the Temp sensor, but I really don’t know much how to proceed there.
I highly doubt it’s the ballast or the color wheel, since you don’t hear any weird noises (constant clicking, whining, whirling, screeching), buy the way the board that was previously replaced, was it the DMD board ( main board that the tech mention)?
Keep us posted for any new developments & good luck.
Remember Knowing Is Half The Battle !

Desertmariner
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Re: No picture or sound, lamp cycles on and off

Post by Desertmariner » Tue Apr 06, 2010 12:18 am

Thanks for reply nightkid,
The board that was replaced was the one that has all the connectors on it for inputs. i think that the the Dmd board is the one with a fan mounted on it's back right behind where the color wheel is located. The digital board where the inoperative fan is located is has two green lights that come on and nothing else. I really wish that it was something simple like a thermastat or temperture sensor. I pull or bridge those connections including the interrupt for the lamp door and nothing changes. Lamp just cycles off and on.
Do you think if the inoperative fan were replaced that it might make it come alive.
Or do you think it could be a symptom of something else.
Does the fan have to come alive for other functions to occur.

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ChubbsTech
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Re: No picture or sound, lamp cycles on and off

Post by ChubbsTech » Tue Apr 06, 2010 3:48 pm

Hello again Desertmariner.
The main function of the fans is to keep the components cool at an ideal temperature predetermined by the factory sensors, when that limit is surpassed its sends an irregular electric pulse to the DMD board. The DMD board detects an irregularity and shuts the tv off. In any case you’ll need to replace the fan in order to discard overheating.
The board that was replaced sound like the analog board ( component cables, coaxial, s-video, etc.) at this point I don’t suspect anything wrong with it until we discard the fan.
Keep me posted, good luck.
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Desertmariner
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Re: No picture or sound, lamp cycles on and off

Post by Desertmariner » Wed Apr 07, 2010 2:32 am

But the question still remains. If the fan doesn't work will that cause the dmd board to not come alive. I can see how the fan not operating would alow the board to overheat in due time. but will it cause it to not "boot up" so to speak.Or is the fan not running symptomatic of some other condition. :roll:
thanks

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ChubbsTech
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Re: No picture or sound, lamp cycles on and off

Post by ChubbsTech » Wed Apr 07, 2010 3:59 pm

In short, yes. A malfunctioning fan will cause the DMD to not turn the tv on. Because as soon as you press the power button the first to scan the entire tv for any malfunction is the DMD board, if it detects an anomaly the tv wont turn on.
Good luck.
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Re: No picture or sound, lamp cycles on and off

Post by Jason1976 » Sun Apr 11, 2010 8:28 am

I have seen a bad lamp come on and then turn off again. try a lamp. 2nd thing that is common in this set is the digital board. could be a power supply or a ballast issue. also if a color wheel isn't spinning right it will make the lamp turn off. It could be almost anything.

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