Problem: Game sound stopped working 2 years ago; owner replaced sound card, didn't fix. Game stopped booting (other than GI turning on) a couple months ago.

BR1 output (switched lamps) on the rectifier board was < 3V. Other TP's metered good. Replaced BR's with larger, replaced all header pins, trifurcon connectors, re-flowed all solder on rectifier board. Everything meters within variances with transformer + rectifier assembly out of cabinet.

On solenoid driver/HV/regulator board, replaced the 150uf/350V HV cap, the 15000uf/35V filter cap, and replaced the LM323K with a EZSBC switch mode replacement (as I have done on over 15 WPC boards with great success).

Fed only J3 into the driver board (all other connectors removed from all boards except the rectifier's 3). Unregulated voltage at TP5 and the new 15Kuf cap is 0.45V (should be 12V). Basically zero voltage out from the regulator at TP1. Exact same symptoms as before rebuilding the rectifier board and part of the solenoid board.

I lifted (and metered) every smaller cap and resistor from the regulator circuit with no net change; so either the filter cap (brand new) or the LM323K replacement --- or something else that is connected via J3 is pulling down the voltage prior to the regulator.

Nothing smells/feels hot anywhere other than the obvious 2 cement resistors on the rectifier board as they should. Any thoughts to find the voltage pull before I pull every pin out of J3 one by one? Thanks!

Thank. I had metered J3 pins 11/12 to pin 10 (or any other grounding pin) with J3 disconnected show +12VDC unregulated, but drop to 0.45V as soon as it's connected to the board. So it's down to cap, regulator (which I already replaced both), or something on J3 itself pulling.