Hello! Just got a Williams flash a few weeks ago as my first machine. I’ve been playing it for awhile but I’ve blown through about 4 fuses in F5. The failure is very sporadic, sometimes during gameplay, it failed right when I put a new fuse in. Most recently fuse didn’t fail but the Rottendog MPU reset.
Troubleshooting to date: Checked all voltages recommended on home pinball repair on the power unit. 5.1V was steady on the 3J6 pins, F5 fuse was receiving around 12.8V. Odd thing is I disconnected every connection except from the 3J1 and 3J2, did some cleaning, put it back together and now I’m getting 11.8V across the F5 fuse but still a consistent 5V on the 3J6. At this voltage is also when the machine reset during gameplay. As far as I can tell the rectifiers are is good condition and putting out proper voltage. I also added the safety fuses to the rectifier.
I can see some bulging on the C11 capacitor but I didn’t think this would affect the F5 fuse.
With the sporadic failure mode, I’m at a loss. My last thought is maybe a pin connection? I was thinking about pulling the trigger on a replacement board but would like to get your thoughts. Thanks!
6A4E10A1-0A6D-4867-8BEC-82DE272743F1 (resized).jpegA17629DA-71AC-49F8-991F-A635059664F1 (resized).jpegD6BCB506-02E3-4324-BFD0-DAB1C963E073 (resized).jpegF2860B27-02E2-4EB7-A33C-35A823FDE6A4 (resized).jpeg