Just been asked to look into a batch of these units which all expired the same day, during power fluctuations and brownouts.
Initial observations are fuse blown, caps all look OK and no signs of distressed components. Bridging the fuse lights the series lamp fully i.e. short present on input side. Main suspects are the pair of 2SK2765 FETs.
The trouble with this design - aprtf rom the obvious lack of a schematic - is the lack of space to access any components. There's arguably a 2mm gap between heatsinks and the main tfmr, with components mounted under an overhang on the 'sinks. To remove for example one of the FETS would require removing an entire heatsink assembly with three semis attached.
Before I embark on this probably uneconomic task, I thought I'd ask on the extremely remote chance that someone may have a schematic for any of this family of MACRON psu's, as deep googling has turned up zip.
Interestingly, on the HiPo website the -4012 is listed as 115/230V while the PSU label states only 230V. There is no sign of even the potential for a voltage selector switch on the pcb trackwork, so I'm forced to wonder if it is one of those auto-sensing dual voltage types which traditionally get confused and die during 240V system brownouts.