I have a Samsung HL-P4663 720p DLP TV. It am using a Motorola 6416 over the HDMI interface.
All of a sudden the screen will go blank, the sound continues, and I can not use the remote control for the TV or the side buttons on the cabinet to control any features.
If I change the channel on the Motorola STB the sound coming from the TV changes normally indicating that the HDMI interface is working fine.
On some occasions I can use the power button on the remote to turn the TV off and then of course the sound also stops.
My only temporary workaround is to unplug the power to the TV. Then plug it back in and all works normally it the failuire occurs again.
Anybody have any ideas on how to fix this problem.

I have a Samsung HL-P4663 720p DLP TV. It am using a Motorola 6416 over the HDMI interface.
All of a sudden the screen will go blank, the sound continues, and I can not use the remote control for the TV or the side buttons on the cabinet to control any features.
If I change the channel on the Motorola STB the sound coming from the TV changes normally indicating that the HDMI interface is working fine.
On some occasions I can use the power button on the remote to turn the TV off and then of course the sound also stops.
My only temporary workaround is to unplug the power to the TV. Then plug it back in and all works normally it the failuire occurs again.
Anybody have any ideas on how to fix this problem.

if you are unable to manually turn the tv off and you cannot see the menu on the screen when you press the menu button, but you can see a faint glow on the screen indicating the lamp is lit, then you will need this:
BP94-02065A Digital PCB or BP94-02140N Analog PCB

I can manually turn off the TV with the button on the front panel but can not turn it back on. The fan is not running and I see no backlighting so it appears that the lamp is not on.
The problem has not happened again for 3 days now and did not happen before if the TV worked normally for an hour or two.
Thank you for your inputs I agree that it was caused by a voltage distribution problem that effected screen display and remote/button actiity but did not effect sound or the HDMI interface.

The cause of the prolem appears to be a voltage regualtor problem somewhere in the HL-P unit.
For two mornings in a row the problem has occured at the same times as my sprinkler turns on so it appears that a quick slight drop in line voltage is the trigger. This mornin it occured 3 times and sure enough I looked out the window and the sprinklers had just turned on. I have not identified the trigger for the line voltage drop in the late afternoon yet.
Last week I switched to pluggin the TV into a different surge suppresson strip and that did not make a difference.
Elite Data and Hammerdwn, Does this information narrow down the possibe failed component and if so what do you estimate its replacement cost to be.

...using a Motorola 6416 over the HDMI interface. All of a sudden the screen will go blank, the sound continues, and I can not use the remote control for the TV or the side buttons on the cabinet to control any features... Seems like digital board ~$230

The cause of the prolem appears to be a voltage regualtor problem somewhere in the HL-P unit.
For two mornings in a row the problem has occured at the same times as my sprinkler turns on so it appears that a quick slight drop in line voltage is the trigger. Jeeze I don't have a clue on that, except checking power supply and ballast caps is a must on all sammy dlps.

Seems like digital board ~$230

Jeeze I don't have a clue on that, except checking power supply and ballast caps is a must on all sammy dlps.

i concur.
caps on the smps could be the cause as well, but that model and the description of the problem, ive have seen so many digital/analog pcb's cause it.
typically, the lamp is lit, there is sound but nothing on the screen but a faint glow, you cannot control the tv functions.
more research into the problem resulted in discovering multiple surface mounted low profile caps failing an esr test on the digital pcb

I have not looked in the back to see if the lamp was lit. I made my judgement based on the fact that I saw no backlighting in almost but not completly dark room. The fact that you have seen the symtom before is encourgaing to me that your diagnosis of the digital or analog PCB is correct.
The problem has not occured this morning when my sprinkler valves turned on.
A capacitor that is starting to leak certainly makes sense as a possible cause.