First of all check IC451 (LA78045) 2 feet and 6 feet power supply voltage, all normal. Test voltage is normal, 5 feet 1 foot and then test the voltage, and essentially normal. No sawtooth waveform observation 1 foot, input, fault is suspected by IC401 (AN5441S). Measurement of IC401 + 5 v and 12 v power supply, 10 were normal. 26 feet voltage is normal also, observation of 26 feet waveform, also normal. 17 feet and 23 feet waveform and observation, found that there's a sawtooth wave, 23 feet but 17 feet without a sawtooth wave, showed AN5441S internal circuits may be damaged, replace AN5441S, troubleshooting.Ru9service manual download site