Blank lcd monitor and no image in viewfinder.

Viewfinder, screen and pictures are blank / black - Nikon ...

https://www.ifixit.com/.../Viewfinder,+screen+and+pictures+are+bla...

iFixitMay 4, 2015 - When I look through the viewfinder or at the lcd it is blank / black. Also when I take a picture and view it on my computer, the picture is blank ...

SONY ' eSupport - There is no picture or a black screen ...

https://us.en.kb.sony.com/.../there-is-no-picture-or-a-black-screen-appear...

Dec 8, 2015 - There is no picture or a black screen appears in the viewfinder or LCDwhen attempting to ... Look to see if an image can be seen in the viewfinder or LCD. IMPORTANT: Some camcorders have both a viewfinder and LCD.

There is no picture or a black screen appears in the ...

was the problem the lense cap, or you do still need assistance?

is your lens cover open for sure?

Follow this procedure to troubleshoot if there is no picture or a black screen appears in the viewfinder or LCD when attempting to record.
NOTES:
* Because each of these steps represents a possible solution to this issue, check the viewfinder or LCD status after completing each step.
* It may be necessary to refer to the operating instructions provided with the camcorder for information on how to perform a task on your specific model.
1. Ensure the lens cap on the front of the camcorder has been removed.
2. Ensure a fully-charged battery is inserted in the camcorder.
3. Ensure the STANDBY/LOCK switch is set to the STANDBY position.
4. Turn on the camcorder and set it to the CAMERA mode.
5. Look to see if an image can be seen in the viewfinder or LCD.
IMPORTANT: Some camcorders have both a viewfinder and LCD. To conserve power, the viewfinder and LCD will not display at the same time. To use the viewfinder, the LCD must be closed.
6. If the issue is not resolved, reset the camcorder to factory specifications.
NOTE: If the issue is still unresolved after completing the troubleshooting steps, service may be required .

The D40 works the same way SLRs have worked for the past half century. Only recently have dSLRs acquired a "Live-View" capability, where you see the image on the LCD monitor instead of through the viewfinder.

I realize this probably wasn't the answer you wanted to see, but that's the way it is.

Correct, its CCD Imager failure case in your DCR-TRV25E camera.
Sony offers repair of your camera free of cost.
Click Sony Support UK to get details..
Good Luck.

Knowledge Article C116445
There is no picture or a black screen appears in the viewfinder or LCD when attempting to record. Follow this procedure to troubleshoot if there is no picture or a black screen appears in the viewfinder or LCD when attempting to record. NOTES:

• Because each of these steps represents a possible solution to this issue, check the viewfinder or LCD status after completing each step.
• It may be necessary to refer to the operating instructions provided with the camcorder for information on how to perform a task on your specific model.

1. Ensure the lens cap on the front of the camcorder has been removed.
2. Ensure a fully-charged battery is inserted in the camcorder.
3. Ensure the STANDBY/LOCK switch is set to the STANDBY position.
4. Turn on the camcorder and set it to the CAMERA mode.
5. Look to see if an image can be seen in the viewfinder or LCD.
IMPORTANT: Some camcorders have both a viewfinder and LCD. To conserve power, the viewfinder and LCD will not display at the same time. To use the viewfinder, the LCD must be closed.

6. If the issue is not resolved, reset the camcorder to factory specifications.

NOTE: If the issue is still unresolved after completing the troubleshootin

This is a known problem with the CCD - Nikon will replace at no charge. Go here: http://www.imaging-resource.com/badccds.html

If you turn on the back LCD, the electronic viewfinder will remain on while in a shooting mode. There is no setting on the camera to use only the back LCD monitor while shooting. If you playback images in the Play mode, only the LCD monitor will turn on. However, if you press the Monitor button while in the Play mode, than the back LCD monitor will turn off. The image will display only in the viewfinder LCD.

Since the viewfinder sees the subject different than the picture taking lens, we recommend using the LCD monitor screen for taking macro pictures. The image previewed on the LCD monitor will be the exact image that is taken.