Hi there, once again I'm in need of an expert opinion on a problem I have with my fh pinball.
Problem: front playfield G.I. Strings (white-violet) burn the 5v fuse (F106) every time I turn the machine on.
History: all G.I. Was working fine on my machine (I have LEDs from comet installed) until Suddenly while playing the front playfield G.I. (Including coin door) turned off. I opened the backbox and found out that f106 tripped. I replaced the fuse but unfortunately it tripped again once I turned on the machine.
Diagnostics I've made so far: 1. I checked all lamps & wiring of the white-violet gi string. Everything seems perfect. 2. I checked to see if any soldering point was connected to ground. No such thing. 3. I Checked for continuity between the fuse holder edges on the Pcb (fuse off - machine turned on). The multimeter gave me a strange sound to my surprise!!! I turned the multimeter to measure VAC between the fuse holder's edges and it showed me 4,7 Volts AC!!! 4. I disconnected J119 & J121 which contained the white-violet G.I. Strings and now I don't have any voltage across f106 edges!
My thoughts on solution: maybe the triac Q12 shorted out??
Please guys I'm in desperate need of advice what to do next....
Thank you!