This has been known to happen on BSD if the long range optos are intermittent; most often there is an issue with the opto board under the playfield (if it only happens after mist multiball). If it happens after other multiballs, it could just be a sticky trough switch.

As for the 24-opto board that is usually problematic, do a quick check to see if that has any obvious issues like the inductor coming off the board, loose connectors.. Next time this happens, you may also want to take the glass off, go in the switch edges test, and do a karate chop motion with your hand on the mist ball's path to see if you trigger that opto switch.

When the playfield is up, the opto board is directly above the round Dracula face insert.

I'm going to agree with kevinleedrum and stress that you check your trough switches in switch test. First question. Does it happen in all the multiballs or just mist multiball? If the mist ball is still locked and you start and end coffin mb and I happens then, then it's not related to the long range opto. But if it requires mist mb, it's likely that opto. I'd start by testing all the trough switches in switch edge test. If the left must trough switch shows a closed switch, then the game will think the last ball drained when it hasn't yet.

I had this issue with another pin. Replaced bridge rectifier Top left on power driver board. Fixed it.

Well I didn't quite get the whole story so my prior advice was probably not accurate. That is if the game doesn't reset or shut off but rather the just flippers quit.

based on posts, bsd has to be one of the most problematic games. endless issues. guess i've been lucky.

This is the start of the problems with the long opto (24" mist ball sensor circuit). As others have mentioned - pull the board out (under the PF about the middle) and reflow the connector pins. Also look carefully at the green inductor for a broken pin, this is VERY common and will cause this intermittant issue.

If the inductor has a broken pin, chip away some of the 'goop' around the broken wire and re-solder it to the board. Then hold it in place with a little hot melt glue. Bad solder around the connectors and this broken inductor is about all you can do to fix this board.

If you still have problems a new board is your only long term fix I'm afraid. You could look for a board from a parted out machine or use one of these:

http://www.homepin.com/bsd.html

This replacement would fix the long opto problems once and for all.

I haven't found BSD to cause any more problems than most other machines of this era. Some other machines cause much more complex problems. Replace the caps and bridges on the solenoid driver board - fix a few burnt GI connectors and sometimes this long opto board and BSD is a very reliable machine.

Some have trouble diagnosing the long opto circuit because it works very differently to other opto circuits so maybe this is why BSD gets a bad name for problems - this is unwarranted.

Man, I love your handle. The AV-8B was the first jet I worked on at McDonnell Douglas. But replacing any bridge for a problem like this would have no affect at all. And, the one in the top left has nothing to do with the 5 VDC power circuit.

If you removed the board, replaced the bridge, reinstalled the board, and the resets went away, then it was removing/reinstalling the board that "fixed" the resets, either by reseating connectors or by creating a stronger ground to the backplane by tightening the screws.

Not trying to bust your balls. Just making sure accurate info is out there.
--
Chris Hibler - CARGPB #31
http://www.Team-EM.com
http://webpages.charter.net/chibler/Pinball/index.htm
http://www.PinWiki.com - The Place to go for Pinball Repair Info

I hired a guy to replace it along with GI connector. Not sure of exact voltages 5 or 12 v. What does optos run on? 12 v? Anyway good clean power to optos is good thing.

I was surprised av8 was available.

The 24" opto board runs on 12 volts but that isn't the issue. It operates different to every other opto in any pinball. It works more like the remote for your TV by sending a stream of 40khz pulses that are received and decoded.

It is because of this method that WMS were able to span 24" without interference issues.

Much the same as your TV remote has very good range and no interference issues usually.

The actual supply voltage to this circuit isn't critical so the usual bridges/caps/burnt connectors make little difference in this case. I guess it's another reason some are lead astray when faultfinding this circuit?

With my first reset issue, I chased my tail for weeks trying to fix it myself. Now I know to just pull the board and take it to a local repair guy who's good with solder gun.

GL

Pull out the board and melt the existing solder on the connector pins - adding a little fresh solder as you do so.

This is called 're-flowing the solder' and it ensures that the connector pins are well connected to the circuit board as - with time - the solder cracks around these pins because of shrinking and vibration from the machine. This can cause intermittent problems that can often be very difficult to find.