Working my way through my bally Star Trek. Have got it to the point of booting (new mpu).

Not yet near playing. The solenoids are doing something odd.

In the solenoid test a number of incorrect solenoids fire.

1 should be outhole but saucer fires
2 knocker - ok
3 saucer - ok
4 left thumper but Drop target fires
5 right thumper but Drop target fires
6 bottom thumper - nothing fires
7 drop target - ok
8 left sling - nothing
9 right sling - drop target
10 - no coin lock in it
11 - flippers - ok

I though it may be a board thing as they all come via U3 on the sdb, but u3 tests fine.

They also almost all come from J5 on the sdb. I tested the headers an they are normal.

Then I tested the connector plugs and there is continuity between the connectors of all of the playfield wires going to the solenoids From J5 as well as J2 pin 5 (knocker) and J1 pin 5 (Outhole). I double checked with my other machines and this is not normal.

I’ve tried to work out from the schematic where all of them could short together but I can’t work it out.

Any tips would be awesome. Thanks.
B5C1FC99-920F-45D3-806B-FC0C7E07D211 (resized).jpeg

Yes, double checked. And it plays the correct Star Trek sound.

I’m not sure how to test the outputs at the pins, but have tested the chips with DMM and they are fine.

When I disconnect pin J5 and put 1 probe on 1 connector and another on an adjacent one I get a continuity beep. I checked on my other machines and they are not like this.

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Ok, not really sure what’s going on. I flipped the playfield over to inspect, and now they are all working. I’m guessing it’s related to connectors as I’ve taken them on an off a few times now.

Bizzare.

I still have continuity between all of the j5 wires but it works.

Switch matrix is screwed up, so that’s tomorrow’s challenge.

I think I’ll just repin all of the connectors first.

Thanks @quench, will do