Because the machine has been used for many years, so the first suspect is the lens dirty or laser tube due to the aging of the machine fault. Use the same type of laser head replacement test machine still cannot read disk. To analyze the machine can not read the TOC for many reasons, such as poor power supply, RF amplifying circuit fault, poor focus tracking servo circuit. Will the VCD machine is connected with the TV start-up, vendor interface, but found a 1cm wide black stripes bottom-up moving slowly on the TV screen, also found that television picture edge slightly distorted phenomenon. Because the TV is normal, it is suspected that the fault phenomenon is caused by the bad VCD power supply.. The measured voltage is VCD + 5V 4.91V, normal. Then remove the main filter capacitor C901 + 5V, check that the capacity is very small. Replace the C901 with the test, and read the dish properly.. Then the original machine head for laser machine, disc reading, playing all normal.a5Wservice manual download site