Everything appears to display correctly, but seems to be unable to recive input signal. ie. no signal on led meter.

Even the LG techinician can't give you no more information abut this fault. If you have any doubt; ask them. Poor fellow, you choose this brand TV.

I do not know how many Thinkvision models are out there, but here is a site that offers manuals you can read online or download.
This is just a page from the manual I found. Here is a link to the manual I found. http://www.manualslib.com/manual/91948/Lenovo-Thinkvision-E54.html#manual
THIS MONITOR WILL APPEAR TO BE NON-FUNCTIONAL IF
THERE IS NO VIDEO INPUT SIGNAL. IN ORDER FOR THIS
MONITOR TO OPERATE PROPERLY, THERE MUST BE A VIDEO
INPUT SIGNAL.
This feature is designed to conserve electrical energy by reducing power
consumption when there is no video input signal present.when there is no
video input signal present.When there is no video input signal, this monitor,
following a time-out period,will automatically switch to an OFF mode. And the
LED will turn orange. This reduces the monitor's internal power supply
consumption. After the video input signal is restored, full power is restored
and the display is automatically redrawn. The appearance is similar to a
"Screen Saver" feature except the display is completely off. The display is
restored by pressing a key on the keyboard, or clicking the mouse. Lenovo ThinkVision E54 User Manual

seems like capacitor problem, chack them and if thay have exploded replace them.

Make sure you have selected the correct INPUT. Many TVs have several from which to choose. Locate the INPUT or A/V button on the TV or remote. Press it once and wait up to 3 seconds to see if the picture appears. Repeat to cycle slowly through all inputs until picture appears. Some TV / remotes have buttons labeled AV1, AV2, AV3, etc. or similar do go directly to the specific input as opposed to cycling as above. Press each - one at a time - and wait up to 3 seconds for picture to appear.
If unable to display a picture, check A/V cables at cable box and TV. Note which input is being used on the TV for the cable box. Then select the same AV input on the remote that is being used on the cable box.
If still no picture, contact cable company / Verizon for service.

Normal 0 false false false MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} Hello,

The picture board on your monitor is malfunctioning, since the power led or button is on and it randomly stop the dispaly signals, it means the picture board of your monitor has developed fault.

The best thing for you to do now is to take the monitor to a local repairer within your vicinity to help with the replacement of the picture board because the fault is not something you can fix yourself, in order not to complicate issues.

Take care.

You seem to have a faulty oscillator.

The word UNLOCK may appear in the display if there is a problem receiving a digital audio signal. Follow the steps below to troubleshoot this issue.

1. Ensure the correct input is selected to receive the Audio/Video (A/V) from the appropriate source.
2. Ensure a digital cable is connected to appropriate DIGITAL jack.
3. Ensure the other end of the digital cable is properly connected to the A/V source.
4. Ensure the A/V source is set appropriately to output a digital signal.
NOTE: The A/V source may have a DTS setting that needs to be turned on, or a DPCM setting that needs to be set toDolby Digital .

you need a new video card. it is powering down becuase it is not reciving any signal from you computer. if you are useing onboard video (vga) get a pci video card if you are useing a pci card try puting it in a dfrent slot.