NEC PLASMA MONITOR MODEL PX-42VM2G TURNS ON FOR ABOUT 2 SECONDS LIGHT GOES GREEN , THEN SOUNDS LIKE A RELAY CLICKS IT OFF THEN IT AUTOMATICALLY GOES INTO STANDBY,

SOURCE: NEC Plasma Sync 42MP3 Problem

Hi, This model has some design flaws and yes NEC admitted to them a year ago. The problem with your monitor (hopefully) is a bad power supply. Have a Tech with a voltage tool check the boards as well as the connections Reason, this monitor generates a lot of heat ( no cooling fans) primarily at the power supply and sits there. So the wires tend to go weak by the heat build up. What the problem is the power is not going to the correct board in the right voltage. hope this helps out!!!

SOURCE: nec px-42vp4a that turns off

Hello. I have the same issue with my px-42vp4a. Did you figure out the problem. Email me with you did. [email protected]. Thank you. Paul

SOURCE: NEC PX-42VP4G Power supply

Check to be sure that there is no voltage on the input line. You don't indicate what input you are using. Since the set appears to work without an input connected, try looking at the input cable. Also, if the problem is internal to the set, shorting the input jack would cause the same behavior. Please update this with what you find.
Dan

SOURCE: nec 42'' plasma

Try holding down the 'INPUT SELECT' button, then press the power button on, on the tv at the same time.

SOURCE: NEC PX-42VM3A 42" Power problem

I have read that this has been fixed with little more than a hard reset. This means just unplug your set for 10 minutes or so and let all the power seep out of the boards and capacitors, then plug it back it.

If that didn't fix it, your unit needs servicing. If you are handy here are some troubleshooting steps:

Check the fuse at Y-Sustainer pcb.
If blown do not replace. Look instead at scan converter boards. They are connected between y-sus & plugs from display (left side with face down, back open). Look for signs of 'burning' at upper and lower long boards. If any imperfections are found, replace all three boards: Y-sus, up & low scan.
If fuse was okay, check power supply for bloated capacitors (big board in middle of set).

I hope that helps.