Reverse engineering has given me this schematic, but no clue to actual voltage from the 418Q1 regulator. It is powering switched mode voltage sensing control circuitry from a 12V battery charger.
Any insights or strategy to progress gratefully welcome.
At the moment the output voltage from the regulator just tracks the input voltage up to 14v, I haven't taken it higher. When the VAC is supplied to the Switched Mode PSU it constantly trips into over voltage mode and resets every few seconds or so. I think this is from the 431 Zener detecting the over voltage in the control circuit supply and tripping the opto.