I have a Nextar MP007 mobile dvd player it plays the disc but there is no video just audio, i get a blue screen cleaned the lens still no video ?

Did you try to clean the lens of your optical reader? A typical product is selle dy Amazon and most retail stores

Memorex CD and DVD Lens Cleaning Kit


Tutorial to use a cleaner is shown in youtube

How to Clean CD DVD Laser Lens in Computer

How to clean DVD or CD player or recorder lens Sony RCD W500C

how to clean car audio player


and much more, just do a google search for

Youtube Clean Car DVD Lens

A. Did you try a second disk to make sure the disk isn't bad?

B. Is the DVD a new format like HD, 3D or Blu-ray? if so it won't work.

If you can play a DVD, the nav disc is dirty or worn. Try gently cleaning it with a flat screen tv cleaning solution and try again. If a DVD won't play, the read head in the player is either dirty or shot - you should have an A/V shop try to clean it, as replacing the unit is $$$$$.

hi there.
it might just be a bit of dust on the inside laser.
Step 3 Laser Lens Cleaning

1. Locate the lens on the disc drive.
2. Make sure that there is no dust on or near the player and area you are working on. ...
3. Dip one end of a cotton swab in rubbing alcohol.
4. Lightly dab the swab on the lens. ...
5. Let the lens dry before replacing the top plate of the DVD player.
6. or just buy your self a disc cleaning laser disc.
7. How do you clean the laser on a DVD player?
   To maintain your DVD player, occasionally unscrew the player's case, so you can get at the lens to clean it. You need a screwdriver, canned air or a soft brush, a foam swab or camera-lens cleaner, and lens cleaning fluid from a camera store
   
   read up some more at this link.
   

How to Maintain Your DVD Player dummies

I have the same problem. did you solve it?

{: ) If you have been playing DVD normally before on your Tahoe, and now you read error messages, it could be the player or the disc at fault. Most of the time it is the disc at fault. As much as possible, the discs shoul be clean and scratch free, not warped, and compatible to your player. Avoid using discs with paper label. Try a known good DVD disc and observe for any progress.
Just in case it's the first time you try and you have a navigation radio, check again your RPO lists. and look for a UVB listed on the RPO sticker. Or simply check the DVD symbol on the left lower corner of the radio, which indicates that it is capable of playing DVD audio or video.

There really isn't anything you can do yourself, other than cleaning the lens using a cd/DVD player lens cleaning disk. Also check that the disks you are using are clean and free of scratches. If the player still doesn't work right, you will have to get it serviced at the dealer. Some electronics repair shops will also service these players, but you will have to remove it from the vehicle yourself. Hope this helps. Good luck.

the problem is dirty lens, try use a dvd/vcd lens cleaner, or manually clean the lens using damp cotton buds.

The laser lens could just be dirty or the laser could have burned out. you can try one of the lens cleaning discs available at most electronic stores or your local Wal-mart.

bigc

try cleaning the unit with a disc cleaner.and make sure all dvds are clean