Repair #4 - Star Trek The Next Generation diverters dead (STTNG)

Yet another star trek issue :(

This time, the diverters under the playfield do not work. The symptom is that balls continually load onto the playfield, shoot into the lock, come out the left popper, and repeat, forever. This happens when one or more of the diverters are not diverting the ball to the correct popper(s). The game wants to preload three balls. One into each gun popper and one into the left popper to speed up game flow when a subway hole is shot. The fact that it runs eternally indicates that one or more of these balls are not arriving at their intended destinations.

So, first, let's test each solenoid. Go into solenoid test and fire them one at a time. You can hear them fire. When I get to top diverter, it does not fire. I raise the playfield and inspect the linkage and look for disconnected wires. Looks fine. I close coindoor with playfield raised, and its firing the diverter just fine. (WTF?) Ok so we lower the playfield thinking maybe it's fixed. Again, diverter won't fire. Raise playfield, diverter fires. Odd. Must be a loose wire somewhere.

To try to help determine which of the two wires is loose, I go back to solenoid test. Let's try the next solenoid in the coil chart. The bottom diverter. It also fires with playfield up, does not fire with playfield down. So I trace the purple / green wire down. It runs to the back drop target. Run the target up and down tests. The target up runs with playfield in either position. The target down coil does not run when playfield is down but does run when the playfield is up. Ok, so the last working coil is the drop target up solenoid. Look at the wires on that, and sure enough, one has come loose. It is touching only when playfield is raised but not when lowered. Solder the wire back on and all is fixed.