Quoted from someotherguy:This one was locking on all the coils upon boot up due to the MPU issue; and yes, without doubt someone had either severely over-fused it or had shorted the fuse clip to "fix" it. No other way it could have burnt those coils like that. One thing that was interesting is I could boot it with the solenoid fuse out, then install it after it booted, and play a game. Next power cycle, *pow* there goes the fuse.. game like that is where using the light bulb rig in place of the fuse helped save a lot of frustration. Keep working at it until the light bulb doesn't come on anymore; no more wasted fuses..
Sounds like an issue with the blanking circuit. I had the same problem intermittently for years on my BK, and the solution wound up being the 555 timer, a tantalum cap, and a transistor (all in the blanking circuit region of the mpu) that needed to be replaced to fix it. Basically the blanking signal was going high as soon as the game was booting, causing all the coils to lock on upon boot-up. In my case it was blowing the 2.5a solenoid fuse due to the coils locking on. I also found i could replace the fuse after the game booted and it would work fine for hours. Weird problem.