I'm working on a Firepower and everything works except the blanking curcuit. When the game is turned on all coils fire one time and then the game goes into attract mode. It will start and play a game, but there are no displays due to the faulty blanking circuit. I've replaced IC7, IC23, Q5 and C32. I checked and rechecked all traces in the circuit and I can't find the fault. In attract mode TP4 reads 5volts.

What am I missing here?

Jason

All the coils fire simultaneously the instant the game comes on. TP4 should be at zero after the board boots, but it stays at 5v. It is my understanding that if the blanking circuit was working properly, TP4 would be at 0v after it booted up.

Jason

I finally had a chance to get back to this. There was a trace broken between TP4 and the interconnect. Thank you for the help.

Now the blanking stays logic low and of course, it won't boot now. All blanking chips and cap on the mpu are new as well as sockets.

Back to square one.

Jason

I'm Finally getting back to this board. I replaced IC23 and IC7 sockets with pinstrips and put in new chips. Blanking does not go HIgh. I tried testing with Andres Test and Siegecraft's Solenoid tester. the LEDs on the tester do not behave like others I've seen in videos. I've linked a video of mine. I'm clueless as to what is going on now.

Can Someone please help.