Audio Systems: Sony Cd car stereo error code, sony stereos, laser pickup

Question
I have a sony cd car stereo.  I let my brother use my car and now he returned it to me and when I put a cd in it gives a error code of 4.  If I eject the cd several times it will play.  What is a err 4?  

Answer
Chemo,
The error 4 in most Sony stereos 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.

TOM,
T&D ELECTRONICS
tdeser@zoominternet.net