I had a similar issue with my Flash Gordon. Turned out that a wire on a different switch in the same column on the switch matrix had broken off.

First check the trough switch itself for broken wires. Also, make sure the switch is gapped properly, and the contacts are making good contact. Clean the contacts by holding a dollar bill or business card in between them and gently pulling it out while you press the contacts together. Repeat a few times.

If that doesn’t work, next look at the switch matrix diagram in the manual. If you don’t have one, you can get a copy from ipdb.org. Examine each switch in the same column and row as the trough switch. Look for broken wires that have come off the lugs.

If still nothing, report back. It could also be a connector in the back box, but that is a bit more involved, so check the easier things first.

Switch matrix issues are fun, when they aren't driving you crazy.

The way the switch matrix works is that the computer in the back box sends an electrical signal down each of the columns, one after the other, in succession. When it gets to the end, it repeats. That signal travels down the whole column since each column is connected by a common wire. If any switches are closed, the signal passes through that switch and then along the row, heading back to the computer in the back box. Each row is also connected by a common wire. The computer is "listening" to each row to see if a signal is returned. It knows which switch is closed when it "hears" a signal from the row corresponding to the switch AT THE SAME TIME it is sending the signal down the column that corresponds to the switch.

So, let's say that at the time the computer sends a signal down the third column from the left, it hears a signal from row I-7 (the last row), it then knows that the outhole switch is closed.

Because each column is connected by a common wire, and each row is connected by a common wire, then a break in the wire, either in the column or row, can cause switches not to register. The tricky thing is that the switches are not necessarily wired in the same order that they appear on the matrix. (That was a hard concept for me to get my head around until I finally did.) So, for example, and I'm making this up, but row I-7 might be wired from switch #16 to #40 to #8 to # 24, etc. Again, I'm making it up just to demonstrate that it may not go in order, but it is all connected.

Now to your issue. Given that two switches are out in the same row, I would first check all the switches in that row to see if a wire broke off one of the metal lugs on the switch. Depending upon where it happens, and it might not necessarily be on the outhole or pop bumper switch, it could cause both of those switches not to work since the signal can't return. For example, and again I'm making this up, what if the wire started on the pop bumper, went to the outhole, then went to the slam -- but was broken right when it was supposed to touch the slam. Nevertheless, the wire from the slam to the rollover was intact, and the wire from the rollover to the target was intact, and the wire to the backbox was intact. Then, you would have all of those latter three switches working, but not the outhole or pop bumper.

I really hope that makes sense. It didn't for me for the longest time until I had enough of these issues that I just finally started to get it.

So, first check all switches and the wires in that row. Then report back.