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Sir Xander . . . . . .
Your findings so far has confirmed your units frontal portion is good down to my GREEN line of demarcation.
Do you now have your stamped and validated learners permit, as this troubleshooting / analysis might be quite involved, with it being one quite hefty power supply.
Its having to supply dual 30 V supplies at 8 amps and an 18V one at 2.5 amps, with that last one dividing and sub dividing down as many times as the tentacles on two octopi.
The units two SMPS IC's are shown on this one of a kind, custom 1 piece schema, of that units power supply.
( Power flow is from far right to left )
I suspect some faulty section loading down the system so greatly that sensing / overload circuitry will not even let one or both of the SM power supplies start up.
Thus, reflecting your full raw DC power voltage not even being pulled down.
Start by passing us the voltages being read on all the pins of IC5799 minor SM regulator IC and then move to IC5701 major SM regulator IC.
Negative voltage ground referencing for all of this metering will be the negative of your initially mentioned C57112 . . . . .with 560 ufd filtering at 200 V, already telling you that this unit has some HEFT.
Voilà . . . . .le Schématique . . . . . .c'est magnifique . . . . . .non ?
73's de Edd
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