1. Image does not exist and there is no sound, raster speckled thick.
2. No picture no sound, or otherwise.
3. Channel switching the channel itself.
4. Image blocking white or blue.
How to check the tuner and the IF is to remove the tuner from the PCB and connected by cable to the IF path, BM and Ground, then prepared using the pin on the tuner. Then the television was turned on, the antenna is connected to the antenna socket, and RV or potensio rotated slowly to choose the television channel when the tuner is in normal condition, the signal from the antenna to be acceptable, the picture and sound, and the channels do not move themselves. To damage its own channel switch and checked the normal manner stated above, the location of damage on the section of the program.