johnieG, is it relatively common to rebuild the logic boards? If its the one diode, it seems like an easy replacement. Have you done these before?
not as simple as it appears, the problem is when the zener diode goes bad, it usually destroys multiple components on the circuit board, & yes I have been repairing these units for about 10 years now, ( and no I won't divulge my my hard-earned trade secrets
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