Color Wheel, DMD Board, or is my new Phillips bulb junk

Samsung HLT5075SX/XAA 50" DLP HDTV - approx 5 years old 7100 hrs

2 months ago my bulb blew...

Thinking I would save some money, I used a generic bulb - it lasted 2 weeks and blew

Thinking it was bad luck, I had them swap it out under warranty - it last 1.5 weeks and blew

There were no other problems with the TV, no noises, never shut down on its own... etc.



I decided to buy an OEM Phillips bulb and a new ballast as a last ditch effort to save my TV


The new ballast and new bulb are in, the TV starts right up, but now it shuts off after it gets warm (approx 10 min). All three lights flash, and won't turn back on unless you unplug, and plug back in, then it only lasts about 1-2min before shutting down with the same 3 lights flashing.


In order to troubleshoot, I bypassed the temp sensor, and the bulb door switches, reset the bulb timer, swapped back in the original ballast....Also, unplugged all the inputs and TV still acts the same, no change...during all this troubleshooting there were 2 days where the TV worked perfectly, but then returned to this behavior....


Now I'm stuck...I don't know if the bulb is crap after it gets hot and I need to get 'another' bulb...or is something else gone wrong.

The fans work, all dust has been removed, the color wheels spins and makes no abnormal noises...



FYI the DMD board was replaced approx 1 year ago when I called samsung about the 'white spots' issue...

Discount-Merchant is willing to help by swapping out my new Phillips bulb with another...just so that we can rule out the bulb...since thats the only 'different' thing since this problem started to occur

some more testing before I send back this bulb...

Disconnect Temp Sensor while running (simulate bad temp sensor, or overheating):
1 light flashes on front and tv shuts completely off (fans/etc.)

Disconnect Door switch while running (simulate bad door switch, or open door):
2 lights flashing, tv shuts completely off (fans/etc.)

Pull out the bulb while running(simulating bad bulb):
3 lights flashing, fans and color wheel continue to run -> this is the exact symptom I see after the bulb is heated up on my TV

Pull out the ballast sensor wires while running (simulating either bad bulb/or bad ballast):
3 lights flashing, fans and color wheel continue to run -> this is the exact symptom I see after the bulb is heated up on my TV

So... i'm fairly confident that a new bulb will do the trick. Like I said, the new ballast and the old working ballast had the same results, and the only thing different from when my TV worked perfectly is the bulb. I hope thats it...if this is not, I'm buying a new TV! Since my fans and color wheel are still running when the TV shuts down, I don't think my problem is with one of those three.

Update you in a few days when the new bulb comes in