Hi from Norway!

I've been having trouble with my Firepower for the better part of a year now, so it is about time I consult with the experts here on Pinside.

The backstory is as follows. When I first got the game I switched it on and it burnt a transistor on the driver board right off the bat, and the solenoid on the top left pop bumper with it. At that point I just wanted to play, and my confidence with soldering on boards was not really there, so I switched the solenoid for an aftermarket one and went ahead and splashed out on new boards - both mpu, driver and psu - from http://www.pinballpcb.com/, thinking that would solve the problem.

It did - for a little while.

The recurring problem is as follows. I can play for a while without issues, sometimes even close to an hour, before the game suddenly tilts mid-game. This is always caused by hitting the aforementioned top left bumper. What happens after this is that the game will always trigger the tilt when the ball hits either the top left bumper or the upper top right standup. I have checked the diode on the solenoid and changed the switch.

I have managed to find a temporary fix for this problem. On the driver board I change IC 17 (top right in this picture: http://www.pinballpcb.com/images/MainBoard/ComboDriverLarge.JPG ) and the game works again until the cycle is repeated. One of the strengths of the aftermarket boards is that they use IC's that are currently in production, so my rather embarassing solution has been to stock up on the IC in question and just swap it out whenever it fries. Paradoxically, the aftermarket pcb's from pinballpcb.com also might make this a harder nut to crack, because I suspect the safety tech in them prolongs the life of the pin whereas the original boards really would fry right away.

When IC 17 is replaced, the board checks out fine when I test it with playfield detached. This leads me to think that there must be an error somewhere on the playfield, but I have been tugging at wires, reflowing solder, checking diodes and inspecting visually for a long time now and I haven't been able to locate anything out of the ordinary. I have checked the diode on the solenoid of the top left bumper and I have changed the switch here as well.

The other day I noticed something strange. The fault had kicked in again, so in frustration I played around with switched on the playfield in game over mode. Whenever I triggered the the upper top right standup (which sets off the tilt once the fault has kicked in), this made the lamps in the pop bumpers flash along with my triggering. Which leads me to think there might be a short between the lights and the switch matrix somewhere. But I don't really know and I haven't been able to locate any shorts.

And this is where it stands. Firepower is my first pinball machine (I also have a Farfalla), and I really love the game to bits. As you surely have realised I am not very savvy when it comes to repairing pins, but I am eager to learn, so any input you might have on how I should proceed on this will be much appreciated. What would you do next?

Best,
Arch

Wow! I am very grateful for the excellent feedback here, and especially thanks to Schwaggs for such a thorough reply. Inspired by this, I made a new effort yesterday and I think I might have come a long way in solving the problem.

First, I went over the wiring, tracing all potential wires and looking for shorts. I did find one place where the green/yellow wire was wrapped over the sharp edge of a lamp, but from what I could tell the insulation was not broken. The soldering on the top center target was another issue, and upon pulling the wire it came off, so that was resoldered.

I then turned my attention to the upper top right standup switch. When triggered, even out of play, this switch lights the bumpers AND it also does something that I haven't noticed before. It actually causes a glitch in the score displays! This I really did not like one bit, so I went over the green/yellow wire and the white/purple wires which are attached to it again. I did not find anything out of the ordinary, and no other switches attached to those wires triggered the same fault, so I decided on swapping out the switch. And lo and behold, the error disappeared!

What I really don't understand is this: the diode on the switch checks out fine. Can there be a short within the switch itself somehow? I can not really see how this can happen, but what do I know? Alternatively, I might have inadvertently removed the wiring from a power source when I went over it again, and thus "fixing" the short.

Anyway, the machine now works. It will have to be stress tested, because as I have said before the IC17 burns after playing for a while. But at least the scary lightshow is gone!

It would be great to hear your thoughts on this, guys!

kaston1573 provided the final piece in the puzzle!

I felt, like you guys, that it didn't really add up with the bad switch causing the lamp matrix problems. Somewhere there had to be a connection between the two matrixes, and the more I thought about it I came to the conclusion that the switch could not be the culprit.

Luckily I have a badly messed up spare Firepower playfield that I have been picking parts from in order to restore my machine. This has the lamp wiring intact, which enabled me to compare the area around the pop bumpers to the one in my machine. And, like kaston1573 says, the spare playfield has plastic tubing around the area where the lamp wire enters the pop bumper. On the playfield in my machine, however, there is no tubing!

Inspecting the wiring at the point where it runs under the mounting bracket of the top left pop bumper, I found a small burn mark. Hardly noticeable, but it's there. This is the coil which I replaced when I first got the machine, and I have previously noticed that it hits with a slightly stronger force than the old ones. This might just be what has tipped the scales! When I think about it, it all adds up. Simply due to the rules of the game, the pop bumpers does not light up in gameplay before you hit certain targets, which is why the fault did not kick straight away. The bumper had to be lit simultaneously to the coil triggering.

I don't think that the tubing has ever been there on this particular playfield. The staples on the lamp wiring are all very close to the pop bumper bracket, leaving little room for tubing. I did manage to sneak some tubing around the wires just beneath the bumper brackets though (see picture), and there you go... I managed to play for one and a half hour consecutively! I have never played that long without failure before, so I think I can now consider the machine repaired!

Thanks a lot guys! Couldn't have done it without you!

IMG_3334.png

Thanks!

The game has now been playtested for almost four hours so the fault is clearly fixed. At the same time, cody_chunn's question lingers with me. What is the possibility of a short between the brackets and the coil or the switch? There must be some reason for putting that isolation there, I mean? Thoughts?

Hi guys,

It is with heavy heart I am resurrecting this thread. The problem is back.

To recap: I have a new PinballPCB driver board (http://www.pinballpcb.com/System3-7DriverBoard.html) that keeps blowing the same IC over and over. The chip is in position IC17 and it is a 7406. The failure occurs - usually after a game or two - when the top left pop bumper is activated. The game tilts and the switch matrix is all messed up until I replace the luckily cheap 7406. As you can tell from this thread I battled with the problem for some time until I thought I had found the solution. By isolating the lamp wires going into the pop bumper, the game started working and did so for a year.

Now the problem is back. I have taken the pop bumper apart and further isolated the lamp wire so there is really no way that I think that the switch can short to it now, but the IC keeps on blowing whenever the pop bumper is activated. If not the first time, then the 30th, and the pop bumper is not always lit when it happens. Which leads me to believe that I just got lucky when I thought I had found the problem.

Can it have something to do with the mounting of the driver board? This is an idea I got from this thread: https://pinside.com/pinball/forum/topic/warning-to-rottendog-327-owners-check-it-now The PinballPCB board is not a perfect fit for all fours screws in the backbox. I have the two top screws mounted, and the board basically just hangs there. The IC which keeps blowing is the topmost to the right here: http://www.pinballpcb.com/images/DriverBoard/DriverBoard.jpg
My bracket is different from the one in the picture though, running horisontally rather than vertically. So my question is, does this board need to be grounded through the screws, or can I just elevate it from the bracket by some pcb feet or similar?

If it is not a problem with the board shorting - can it be the switch itself? The pop bumper switch looks ok to me, but don't really know what I am looking at. Can the resistors on the switch blow? Can the switch short to the coil? Any ideas are much appreciated.
Cheers!

Sorry for the late reply. You guys nailed it! The switch in the pop bumper shorted on occasion, causing the problem. Thanks a lot for the answers! Firepower lives again.