NO DISC error on a CD / DVD player. A typical symptom is you insert a disc in the player and after a while; the CD tray opens again with the message referring to no disc being in the system. This can be infuriating because you can see that there is a disc, however, the CD / DVD player cannot.
When the tray is closed, the laser beam emits two long bursts with laser light. The focusing platform moves up or down in an attempt to focus the beam. This is the time when it is looking for a disc. If the laser has failed, then it will not be able to detect a CD and therefore the error message appears.
When this happens, there are two things I do. I normally clean the lens just in case there is dust on it obstructing the laser path. If the problem persists, I check that the laser is functioning.
You should not look into the laser unit directly. That would be stupid. The laser light is bright enough that one can see the diffused red light from a distance obliquely. A piece of paper the size of a standard CD within the tray can also help, because when the tray closes, one can see the diffused red light on the paper. It is often bright enough to be visible from the opposite side of the paper. If the red light is not visible, then the laser has failed.
Many of these were broken back in the 1990s when I was able to fix them. It was either the spindle motor or the laser that failed. These two components are constantly in use and wear the fastest.
Laser diodes do not last forever, especially on the early players manufactured in the 1980s. It would be very surprising to find a player still working from that era.
Most of those units used cheap motors where the brushes wore out within a few years. The laser would fail if the motor failed. The laser diode manufacturing process was not as refined either, and those diodes had a short finite life to them. Most of those early DVD players would be hard to find as they often ended up in landfill.
Many high-end players I’ve seen recently use the same cheap mass-produced drive mechanisms. Moreover, most of those failed within a few years as well. This is a shame, as one would expect high-end players to have better components for the mechanism; however, it is usually the same cheap mechanism found in unbranded supermarket models.
A laser diode, being a semiconductor, fails in an interesting way. It becomes unstable when it reaches the end of its useful lifespan and is about to go bankrupt. Its operation becomes intermittent and can be confusing for the user. It may work one moment and not the next. It might not work for all CDs.
From the user’s point of view the player initially starts becoming temperamental, and then stops working completely and unable to read any disc.
If you have an old player that is getting temperamental, then now is the time to buy a new one. I would highly recommend a Blu-ray CD player. The newer players offer more features and better quality for half the price.
