You could verify the connections shown on the schematic:
Kick Off Bonus Unit wipers (resized).jpg
It looks like there are six wipers (red arrows on the schematic) on the Bonus Unit unless I missed some. All of them connect the common yellow (30) wire to another wire as the Bonus Unit steps through its 30 positions. The schematic is likely drawn with the Bonus Unit in the reset position.

Looking at the schematic in the top center above, in the reset or 0 position the wiper should connect a yellow wire to an 85 or black-white wire. At the bottom of the schematic one of the two wipers should connect a yellow wire to a 21 or blue-red wire. The rest of the wipers make no connection in the reset or zero position. You should be able to verify these connections with your meter if you unplug the game first.

From there you can step the Bonus Unit up one position and check the connections made by the wipers in position 1. Repeat for as many other positions as you want. If the wipers aren't making the right connections you should be able to find where that happens.

Or, you could advance the Bonus Unit until you notice a problem, like both arrows being on. Then shut off the game and check the connections at whatever position the bonus stepper is in against what they should be according to the schematic.

Note that only positions 0-15 are shown in the bottom part of the schematic. There might be another pair of wipers that repeat that same pattern for positions 16-30.

/Mark

Continuity doesn't really tell you much unless you study the schematic and convince yourself there aren't any parallel paths that the meter can detect. What you're looking for is very low (an ohm or less) resistance between points to know that they're connected directly to each other.

Since all of the wipers connect to the same yellow wire it's unlikely that they would be insulated from each other.