Color image blur may be the Y of the brightness signal is not normal, the fault occurs in the video coding circuit AV3169 (U18) and the peripheral circuit, the related circuit see Figure 6. Pilot device measuring U18 11 to 16, 18, 19 feet input 8-bit digital regarded signal waveform of normal, 20, 21 of the input line, the field synchronization signal waveform is normal, but the 31 feet (luminance Y output signal), 33 feet (red color difference signal) and 35 feet (blue difference signals) in spite of the signal wave form, but its amplitude were than normal. Use million with meter U18 pin is DC voltage, found that the analog video signal output end of 31, 35, 33 feet voltage are low, varied in the range of 0.2V to 0.4V, and normally should vary in the range of 0.5V ~ 1.4V; and 38 feet by a patch capacitor C134 connected to the + 5V voltage, doubt C134 caused by the leakage of the pin voltage is increased, then take C134, and check there is leakage problems found, had to expand the scope of the inspection, a census of U18 peripheral components, and finally find out for 39 feet between the ground and the resistance of r159 (180 K) resistance by 180 K increased to more than 500 ohms. With the 180 resistance replacement, the image sharpness is normal and the fault is eliminated..E8uservice manual download site