Can't play CDs in my car. The Unit gives me error code 4

The error 4 in most CD Player is an error that comes up when the laser pickup doesn't read the disc correctly. This happens most of the time because of a dirty lens in the laser pickup. If anyone smokes in the vehicle the smoke may be on the lens causing the error code. Try a wet type CD cleaning disc to see if it helps.

"Error 4" is a mechanical disc loading problem. The disc probably hasn't been seating in the #6 carrier properly, leading to some mechanical interference when it is selected. It would seem to be properly seated now, but next time you have it out you might check it on a perfectly smooth flat surface to be sure it is not warped slightly. Try another disc in that position, one you know to be trouble-free.

I burn a lot of discs for my clients and have never had a problem with the mid or high-grade discs from Taiyo Yuden, and others. Even lesser discs like Ritek perform fairly well. Some brands - usually the no-names - fail right out of the box. One of the problems seems to be that the cheapest discs are pretty thin and subject to mechanical problems like warping.

If you use "economy" discs particularly, be sure to put a label on them. Most of the cheap discs don't have much of a protective coat on top and scratching the top metal foil finish can lead to serious playback troubles as the disc is read by the laser from the bottom.. In addition to telling you what's ON the disc, the label helps protect that critical foil.

Hope helps.