1.ERR05
?First of all, check for the bridge voltage 8V normal search OP2277 No. 1 feet and 7 feet voltage of 7.5V, the normal voltage of 4V at about OP2277 suspected damage, after the replacement [b] instrument [/ b] normal work.
?Open the instrument was found 0.22uF capacitor cracking, no voltage 8V, 7808 Richard breakdown, after the replacement of instruments still ERR05, check OP2277 voltage is not normal, CD4066 burning, and the OP2277 replacement CD4066 after [b] instrument [/ b] normal work .
2. No show
牋 First of all, show no 5V supply voltage normal inspection, inspection 9 foot voltage 4.9V, when the normal voltage should be 0V, suspected IMP707 damage, replaced the normal work of the instrument.
牋 [b] instrument [/ b] boot beep sound, but no show, with oscilloscope measurements show no foot chip strobe signal, bad 74HC139 doubt, after the replacement of normal.
3. DC could not boot
牋 Overhaul the process: the use of law to replace instruments that cause damage to the motherboard, first of all check-voltage 8V to 11.8V, the replacement of 7808 after the restoration of voltage to 7.9V, Measurement 7808 Multimeter with input and output feet feet short, the re-demarcation of the post-[b] weighing indicator [ / b] normal work.　　　　　　　　　　　　　

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