I am helping a friend restore a Bally Paragon. MPU is a new Weebly, new Xpin transformer board, recapped and rebuilt solenoid driver.

Everything was working OK until recently. Machine will not get into attract mode, and the mpu will not go past 6 flashes. No fuses are blown, under PF fuse is fine, f4 is fine.

So, I check things a bit deeper, and I unplug the sound board and start the machine, I get the 7th flash and the machine boots into attract mode.

What on this board could be causing the MPU not to get to the 7th flash? I did order the Big Daddy cap/component kit, but it won't arrive for a few days.

What should I be checking on the board that could be causing this?

Thanks in advance, mk

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Just found this in Pin-wiki:

"One interesting anomaly is that the 7th flash will not occur, if there is a bad 1N4004 diode (CR3) used on -32 / -50 sound boards. On these two sound boards, the +12VDC used on the boards is derived from the +43VDC solenoid voltage, and isolated by CR3."

I'm going to check CR3, (and probably some other components). I'll report the results. -mk

CR3 does test as shorted. I'm going to replace CR3, and install the cap/component kit. I'll report the results when I get to test the board in the machine. Thanks, mk