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DVD troubleshooting checklist

As DVD-ROM drives become standard equipment on many desktops, supporting problems associated with these drives becomes more important. Here are eight common problem areas every tech should be aware of when diagnosing a faulty DVD drive.


DVD-ROM drive problems can be real headaches. Even a small problem can be frustrating—users might see a picture but no sound or sound but no picture, bad sound/picture quality, and so forth. Here is a checklist for eight common DVD-ROM problems that can help you get that sick drive up and running in no time.

DVD system components
Computer DVD-ROM systems usually have four or five components depending on the configuration: a data cable (either SCSI or IDE, depending on your drive configuration), a multicolored power cable, a thin ATAPI cable for sound, the drive itself (shown in Figure A), and possibly a decoder card if your system uses hardware decoding (shown in Figure B).

Figure A


Figure B


What could go wrong?
DVD drive problems usually fall into the following categories:
  • No power
  • Incorrect installation
  • Faulty parts
  • Incompatible driver
  • Bad or no sound
  • Bad or no picture
  • Bad disk
  • Miscellaneous

No power
Before doing anything else, check to see if the drive is getting power. The easiest way to do this is to eject the tray. If there is no response, check for a faulty power cable or connection.

Incorrect installation
While the thought of a faulty installation might insult a pro, I have had to eat my share of humble pie periodically. Make sure that the gray ribbon cable is inserted correctly with the red wire at pin 1. On some drives, it is possible to insert this cable upside down. This goes for the ATAPI cable as well. Next, check the CMOS and ensure the system sees the DVD drive. If you have a SCSI drive, check the SCSI Select Utility. The drive will not work if the system cannot see the drive.

Faulty parts
Bad cables do exist. I once spent hours trying to fix a sound problem, only to find that the manufacturer had incorrectly wired the ATAPI sound cable! Use spare parts to test for faulty equipment through a process of elimination.

Incompatible Windows driver
If the DVD drive shows up in the CMOS but not under Windows, check the software driver and Windows Registry. Download the latest drivers from the manufacturer’s Web site and see if they fix the problem.

A corrupt Windows Registry can also cause DVD drive problems. If you have a good Registry backup, you might try restoring it, but unless you are a Registry wizard, reinstalling Windows might be easier. Running the Windows Setup can also refresh corrupted files while keeping your data intact. Get a reliable backup, however, before you do this.

Bad or no sound
If there is no sound, make sure the ATAPI cable is correctly connected and is not faulty. Distorted sound may be fixed by enabling Direct Memory Access (DMA) under Windows. You can also try disabling multiple languages.

Bad or no picture
If there is no picture, make sure that all video cables are correctly connected. Typically, a video cable starts from the video card and terminates at the DVD controller card. Another video cable starts from the controller card and terminates at the monitor. A choppy display may be fixed by enabling DMA. If the picture is distorted, set the menu to 4:3 for monitors and 16:9 for a digital TV. If you cannot see subtitles, ensure the feature is turned on and the disk actually has subtitles.

Bad disk
Four scenarios are possible in terms of a faulty disk. They are a:
  • Poorly mastered disk
  • Dirty disk
  • Scratched disk
  • Warped disk

With a poorly mastered disk, there isn’t much you can do but to get it exchanged under warranty. A dirty disk can be cleaned with a soft cotton cloth. Rub the shiny surface back and forth instead of rubbing in circles. Some scratched disks can be repaired using special chemical solutions.

If you suspect a warped disk, place it on a flat surface with the shiny side up. Press down one edge with a finger and see if the opposite edge lifts up (concave-up test); also, press the edge of the hole in the center (concave-down test). Use the glass top of a photocopier or a scanner if you have trouble finding a very flat surface.

Miscellaneous
Sometimes, the disc tray can become warped due to overheating. On one occasion, I saw a warped CD-ROM disk tray on a server. Below its bay were six vertically installed SCSI RAID hard-disk drives, all “cooking” the poor CD-ROM drive.

Another headache lies with “Country Code” or “Anti-Copy Code” issues. When DVD player software such as Mpact Mediaware or Software CineMaster is installed, a Country Code must be selected. Since the code is burned into the disk, a DVD disc purchased in Australia may not play in the United States and vice versa.

Condensation can also affect both the player and the disk. If you suspect condensation might be the culprit, try cleaning both or wait one to two hours before trying again.

DVD burners
Many DVD burners have amber LEDs that may occasionally flash in a sequence of one, two, or three flashes. A series of single flashes often indicates a higher-than-acceptable internal temperature. The drive will usually pause until the temperature returns to normal and then start working again. If the lens or the disk is dirty, you might get a series of two flashes. You will need a special cleaning kit to clean the lens. A series of three flashes typically means that 90 percent of the spare disc area has been used. You will need to reinitialize the disc and repeat the burning process.

The bottom line
DVD problems are resolved by a good dose of patience and perseverance. Hang in there and you will eventually find the culprit.

Share your DVD troubleshooting tips
If you have a great tip for quickly solving DVD problems, post a comment or write to Kyu Rhee and share your experience.

 

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