According to the remote control to change channels without character display. Try a slightly raised accelerating voltage, visible on the screen has a flyback lines. That line tube, field scanning circuit and auxiliary circuit is normal. Considering this machine for bus control color TV. You should check the bus voltage is normal. First measure the microprocessor ICl213 (MNl874876T5H) bus voltage, 28 feet SDAl of 4.7 v, 29 feet SCL1 voltage of 4.3 v, then measuring IC601 (1 ~ A1215AN) 13 feet (SDA1) 7.15 v, 14 feet (SCL1) working voltage of 4.3 v, obviously 13 feet cable working voltage is more than the normal operating voltage. And besides IC601 CPU bus supervise them. And dark balance adjustment integrated circuit IC3401 (TA8889AP). Measuring IC3401 pet-name ruby foot SCL1 voltage of 4.3 V, attending the foot SDAl voltage of 7.15 V, try disconnecting IC3401 attending foot SDAl bus, measuring IC601 13 feet SDAl voltage of 4.7 V is normal, and IC3401 attending foot voltage of 6.7 V. Considering that this bus is linked together, the voltage should be the same, the two lines for inspection. Found from R3404 to break between R631. At the same time also found from R1134 between K631 circuit. With wires connected after commissioning grating returned to normal.Ss3service manual download site